diff --git a/issue.go b/issue.go
index c44881b0..62e248cd 100644
--- a/issue.go
+++ b/issue.go
@@ -232,16 +232,24 @@ type IssueRenderedFields struct {
 // IssueType represents a type of a Jira issue.
 // Typical types are "Request", "Bug", "Story", ...
 type IssueType struct {
-	Self           string `json:"self,omitempty" structs:"self,omitempty"`
-	ID             string `json:"id,omitempty" structs:"id,omitempty"`
-	Description    string `json:"description,omitempty" structs:"description,omitempty"`
-	IconURL        string `json:"iconUrl,omitempty" structs:"iconUrl,omitempty"`
-	Name           string `json:"name,omitempty" structs:"name,omitempty"`
-	Subtask        bool   `json:"subtask,omitempty" structs:"subtask,omitempty"`
-	AvatarID       int    `json:"avatarId,omitempty" structs:"avatarId,omitempty"`
-	HierarchyLevel *int   `json:"hierarchyLevel,omitempty" structs:"hierarchyLevel,omitempty"`
+	Self           string                   `json:"self,omitempty" structs:"self,omitempty"`
+	ID             string                   `json:"id,omitempty" structs:"id,omitempty"`
+	Description    string                   `json:"description,omitempty" structs:"description,omitempty"`
+	IconURL        string                   `json:"iconUrl,omitempty" structs:"iconUrl,omitempty"`
+	Name           string                   `json:"name,omitempty" structs:"name,omitempty"`
+	Subtask        bool                     `json:"subtask,omitempty" structs:"subtask,omitempty"`
+	AvatarID       int                      `json:"avatarId,omitempty" structs:"avatarId,omitempty"`
+	HierarchyLevel *IssueTypeHierarchyLevel `json:"hierarchyLevel,omitempty" structs:"hierarchyLevel,omitempty"`
 }
 
+type IssueTypeHierarchyLevel = int
+
+const (
+	IssueTypeHierarchyLevelEpic    IssueTypeHierarchyLevel = 1
+	IssueTypeHierarchyLevelTask    IssueTypeHierarchyLevel = 0
+	IssueTypeHierarchyLevelSubTask IssueTypeHierarchyLevel = -1
+)
+
 // Watches represents a type of how many and which user are "observing" a Jira issue to track the status / updates.
 type Watches struct {
 	Self       string     `json:"self,omitempty" structs:"self,omitempty"`