diff --git a/.bumpversion.toml b/.bumpversion.toml
index 155bb928..e86f9f2f 100644
--- a/.bumpversion.toml
+++ b/.bumpversion.toml
@@ -1,5 +1,5 @@
 [tool.bumpversion]
-current_version = "0.0.19"
+current_version = "0.0.20"
 commit = "true"
 tag = "true"
 tag_name = "v{new_version}"
diff --git a/README.md b/README.md
index b7d8afcd..e907bbc0 100644
--- a/README.md
+++ b/README.md
@@ -14,12 +14,13 @@ You can see an [application](https://github.com/lfoppiano/structure-vision) in a
 ## Features
 - Show PDF files in a Streamlit application with a simple command
 - Based on the pdf.js library
-- Support showing the PDF with the native pdf.js browser's viewer: "legacy" (with limitations, no annotations, no scrolling, etc..) 
 - Visualize annotations on top of the PDF documents
 - Render text on top of the PDF document, allowing copy-paste
 - Allow to render specific pages of the PDF document
 - Scroll to a specific page
 - Scroll to a specific annotation
+- Allow custom callbacks when an annotation is clicked 
+- Additional support showing PDF documents using the native pdf.js browser's viewer: "legacy" (with limitations, no annotations, no scrolling, etc..)
 
 ## Limitations
 - Tested and developed to support Firefox and Chrome.
@@ -28,6 +29,16 @@ You can see an [application](https://github.com/lfoppiano/structure-vision) in a
 - The component is still in development, so expect some bugs and limitations
 - The streamlit reload at each action may render slowly for complex PDF documents
 
+## Caveats
+Here some caveats to be aware of: 
+- It ss mandatory to specify a `width` to show PDF document on tabs and expanders, otherwise, the viewer will not be displayed on tabs not immediately visible.
+- From version 0.0.16, the behavior for managing width and height has changed: 
+  - If only the height is specified, the PDF document will be shown in proportion with the with proportional based on the PDF dimensions. 
+  - The possibility to show a large view of half the PDF is not available anymore (let's face it, it was not very useful).
+  - If you need to use all the available space and limit the height, you can encapsulate the `pdf_viewer()` into a `st.component(width:...)` setting the width.
+- The `legacy` rendering is not supported on Chrome, due to security reasons.
+
+
 
 ## Getting started
 
@@ -44,31 +55,24 @@ from streamlit_pdf_viewer import pdf_viewer
 pdf_viewer("str, path or bytes")
 ```
 
-### Caveats 
-
-Here some caveats to be aware of: 
-- Is mandatory to specify a `width` to show PDF document on tabs and expanders, otherwise, the viewer will not be displayed on tabs not immediately visible.  
-- The `legacy` rendering is not supported on Chrome, due to security reasons.
-
-
 ### Params
 
 In the following table the list of parameters that can be provided to the `pdf_viewer` function:
 
-| name                    | description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
-|-------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| input                   | The source of the PDF file. Accepts a file path, URL, or binary data.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
+| name                      | description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
+|---------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| input                     | The source of the PDF file. Accepts a file path, URL, or binary data.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
 | width                   | Width of the PDF viewer in pixels. It defaults to 700 pixels. Can set it to string percentage also. For example 90% which will make the pdf render to 90% of the container/window/screen width. If the pdf width is larger than the screen width, it will horizontally scroll.                                                                                                                                                                                                                                                                                                                                  |
-| height                  | Height of the PDF viewer in pixels. If not provided, the viewer shows the whole content.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
-| annotations             | A list of annotations to be overlaid on the PDF. Format is described [here](#annotation-format).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
-| pages_vertical_spacing  | The vertical space (in pixels) between each page of the PDF. Defaults to 2 pixels.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
-| annotation_outline_size | Size of the outline around each annotation in pixels. Defaults to 1 pixel.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
-| rendering               | Type of rendering: `unwrap` (default), `legacy_iframe`, or `legacy_embed`. The default value, `unwrap` shows the PDF document using pdf.js, and supports the visualisation of annotations. Other values are `legacy_iframe` and `legacy_embed` which use the legacy approach of injecting the document into an `<embed>` or `<iframe>`. They allow viewing the PDF using the viewer of the browser that contains additional features we are still working to implement in this component. **IMPORTANT**: :warning: The "legacy" methods **work only with Firefox**, and **do not support annotations**. :warning: |
-| pages_to_render         | Filter the rendering to a specific set of pages. By default, all pages are rendered.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
-| render_text             | Enable a layer of text on top of the PDF document. The text may be selected and copied. **NOTE** to avoid breaking existing deployments, we made this optional at first, also considering that having many annotations might interfere with the copy-paste.                                                                                                                                                                                                                                                                                                                                                       
-| scroll_to_page          | Scroll to a specific page when the component is rendered. Default is None. Require ints and ignores the parameters below zero.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
-| scroll_to_annotation    | Scroll to a specific annotation when the component is rendered. Default is None. Mutually exclusive with `scroll_to_page`. Raise an exception if used with `scroll_to_page`                                                                                                                                                                                                                                                                                                                                                                                                                                        |   
-
+| height                    | Height of the PDF viewer in pixels. If not provided, the viewer shows the whole content.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
+| annotations               | A list of annotations to be overlaid on the PDF. Format is described [here](#annotation-format).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
+| pages_vertical_spacing    | The vertical space (in pixels) between each page of the PDF. Defaults to 2 pixels.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
+| annotation_outline_size   | Size of the outline around each annotation in pixels. Defaults to 1 pixel.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
+| rendering                 | Type of rendering: `unwrap` (default), `legacy_iframe`, or `legacy_embed`. The default value, `unwrap` shows the PDF document using pdf.js, and supports the visualisation of annotations. Other values are `legacy_iframe` and `legacy_embed` which use the legacy approach of injecting the document into an `<embed>` or `<iframe>`. They allow viewing the PDF using the viewer of the browser that contains additional features we are still working to implement in this component. **IMPORTANT**: :warning: The "legacy" methods **work only with Firefox**, and **do not support annotations**. :warning: |
+| pages_to_render           | Filter the rendering to a specific set of pages. By default, all pages are rendered.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
+| render_text               | Enable a layer of text on top of the PDF document. The text may be selected and copied. **NOTE** to avoid breaking existing deployments, we made this optional at first, also considering that having many annotations might interfere with the copy-paste.                                                                                                                                                                                                                                                                                                                                                       |
+| scroll_to_page            | Scroll to a specific page when the component is rendered. Default is None. Require ints and ignores the parameters below zero.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+| scroll_to_annotation      | Scroll to a specific annotation when the component is rendered. Default is None. Mutually exclusive with `scroll_to_page`. Raise an exception if used with `scroll_to_page`                                                                                                                                                                                                                                                                                                                                                                                                                                       |
+| on_annotation_click       | Callback function that is called when an annotation is clicked. The function receives the annotation as a parameter.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
 
 ### Annotation format 
 The annotations format has been derived from the [Grobid's coordinate formats](https://grobid.readthedocs.io/en/latest/Coordinates-in-PDF/), which are described as a list of "bounding boxes".
@@ -91,6 +95,42 @@ Here an example:
 
 The example shown in our screenshot can be found [here](resources/annotations.json).
 
+### Custom callback for clicking on annotations
+
+```python
+from streamlit_pdf_viewer import pdf_viewer
+
+annotations = [
+    {
+        "page": 1,
+        "x": 220,
+        "y": 155,
+        "height": 22,
+        "width": 65,
+        "color": "red"
+    },
+    {
+        "page": 1,
+        "x": 220,
+        "y": 155,
+        "height": 22,
+        "width": 65,
+        "color": "red"
+    }
+]
+
+def my_custom_annotation_handler(annotation):
+    print(f"Annotation {annotation} clicked.")
+
+pdf_viewer(
+   "path/to/pdf",
+   on_annotation_click=my_custom_annotation_handler,
+   annotations=annotations
+)
+
+```
+
+
 ## Developers notes
 
 ### Environment
diff --git a/streamlit_pdf_viewer/__init__.py b/streamlit_pdf_viewer/__init__.py
index 202084fa..4083f7e2 100644
--- a/streamlit_pdf_viewer/__init__.py
+++ b/streamlit_pdf_viewer/__init__.py
@@ -1,7 +1,7 @@
 import base64
 import os
 from pathlib import Path
-from typing import Union, List, Optional
+from typing import Union, List, Optional, Callable
 
 import streamlit.components.v1 as components
 import json
@@ -39,7 +39,8 @@ def pdf_viewer(
         resolution_boost: int = 1,
         scroll_to_page: int = None,
         scroll_to_annotation: int = None,
-):
+        on_annotation_click: Optional[Callable[[dict], None]] = None,
+    ):
     """
     pdf_viewer function to display a PDF file in a Streamlit app.
 
@@ -59,6 +60,7 @@ def pdf_viewer(
     :param resolution_boost: Boost the resolution by a factor from 2 to 10. Defaults to 1.
     :param scroll_to_page: Scroll to a specific page in the PDF. The parameter is an integer, which represent the positional value of the page. E.g. 1, will be the first page. Defaults to None.
     :param scroll_to_annotation: Scroll to a specific annotation in the PDF. The parameter is an integer, which represent the positional value of the annotation. E.g. 1, will be the first annotation. Defaults to None.
+    :param on_annotation_click: A callback function that will be called when an annotation is clicked. The function should accept a single argument, which is the annotation that was clicked. Defaults to None.
 
     The function reads the PDF file (from a file path, URL, or binary data), encodes it in base64,
     and uses a Streamlit component to render it in the app. It supports optional annotations and adjustable margins.
@@ -123,6 +125,12 @@ def pdf_viewer(
         scroll_to_page=scroll_to_page,
         scroll_to_annotation=scroll_to_annotation
     )
+
+    # Execute the custom callback function
+    if component_value and 'clicked_annotation' in component_value:
+        clicked_annotation = component_value['clicked_annotation']
+        if on_annotation_click is not None and callable(on_annotation_click):
+            on_annotation_click(clicked_annotation)
     return component_value
 
 
diff --git a/streamlit_pdf_viewer/frontend/src/PdfViewer.vue b/streamlit_pdf_viewer/frontend/src/PdfViewer.vue
index 448da9b5..dbd9e25b 100644
--- a/streamlit_pdf_viewer/frontend/src/PdfViewer.vue
+++ b/streamlit_pdf_viewer/frontend/src/PdfViewer.vue
@@ -2,12 +2,20 @@
   <div id="pdfContainer" :style="pdfContainerStyle">
     <div v-if="args.rendering==='unwrap'">
       <div id="pdfViewer" :style="pdfViewerStyle">
-      <div id="pdfAnnotations" v-if="args.annotations">
-        <div v-for="(annotation, index) in filteredAnnotations" :key="index" :style="getPageStyle">
-          <div :style="getAnnotationStyle(annotation, index)" :id="`annotation-${index}`"></div>
+        <div id="pdfAnnotations" v-if="args.annotations">
+          <div
+              v-for="(annotation, index) in filteredAnnotations"
+              :key="index"
+              :style="getPageStyle"
+              @click="handleAnnotationClick(annotation, index)"
+          >
+            <div
+                :style="getAnnotationStyle(annotation, index)"
+                :id="`annotation-${index}`"
+            ></div>
+          </div>
         </div>
       </div>
-      </div>
     </div>
     <div v-else-if="args.rendering==='legacy_embed'">
       <embed :src="`data:application/pdf;base64,${args.binary}`" :width="`${args.width}`" :height="`${args.height}`" type="application/pdf"/>
@@ -55,6 +63,16 @@ export default {
       })
     });
 
+    const handleAnnotationClick = (annotation, index) => {
+      // Convert the Proxy object to a plain object
+      const serializedAnnotation = JSON.parse(JSON.stringify(annotation));
+
+      // Send data to Streamlit
+      Streamlit.setComponentValue({
+        clicked_annotation: { index, ...serializedAnnotation },
+      });
+    };
+
     const renderText = props.args.render_text === true
 
     const pdfContainerStyle = computed(() => {
@@ -377,6 +395,7 @@ export default {
 
     return {
       filteredAnnotations,
+      handleAnnotationClick,
       getAnnotationStyle,
       pdfContainerStyle,
       pdfViewerStyle,