diff --git a/src/tests/account/test_account.cairo b/src/tests/account/test_account.cairo
index 2ca9550a8..cef5a31e3 100644
--- a/src/tests/account/test_account.cairo
+++ b/src/tests/account/test_account.cairo
@@ -101,7 +101,7 @@ fn test_constructor() {
     let mut state = STATE();
     Account::constructor(ref state, PUBLIC_KEY);
 
-    let event = testing::pop_log::<OwnerAdded>(ZERO()).unwrap();
+    let event = utils::pop_log::<OwnerAdded>(ZERO()).unwrap();
     assert(event.new_owner_guid == PUBLIC_KEY, 'Invalid owner key');
     utils::assert_no_events_left(ZERO());
 
@@ -447,10 +447,10 @@ fn test_public_key_setter_and_getter() {
     // Set key
     PublicKeyImpl::set_public_key(ref state, NEW_PUBKEY);
 
-    let event = testing::pop_log::<OwnerRemoved>(ACCOUNT_ADDRESS()).unwrap();
+    let event = utils::pop_log::<OwnerRemoved>(ACCOUNT_ADDRESS()).unwrap();
     assert(event.removed_owner_guid == 0, 'Invalid old owner key');
 
-    let event = testing::pop_log::<OwnerAdded>(ACCOUNT_ADDRESS()).unwrap();
+    let event = utils::pop_log::<OwnerAdded>(ACCOUNT_ADDRESS()).unwrap();
     assert(event.new_owner_guid == NEW_PUBKEY, 'Invalid new owner key');
     utils::assert_no_events_left(ACCOUNT_ADDRESS());
 
@@ -488,10 +488,10 @@ fn test_public_key_setter_and_getter_camel() {
     // Set key
     PublicKeyCamelImpl::setPublicKey(ref state, NEW_PUBKEY);
 
-    let event = testing::pop_log::<OwnerRemoved>(ACCOUNT_ADDRESS()).unwrap();
+    let event = utils::pop_log::<OwnerRemoved>(ACCOUNT_ADDRESS()).unwrap();
     assert(event.removed_owner_guid == 0, 'Invalid old owner key');
 
-    let event = testing::pop_log::<OwnerAdded>(ACCOUNT_ADDRESS()).unwrap();
+    let event = utils::pop_log::<OwnerAdded>(ACCOUNT_ADDRESS()).unwrap();
     assert(event.new_owner_guid == NEW_PUBKEY, 'Invalid new owner key');
     utils::assert_no_events_left(ACCOUNT_ADDRESS());
 
@@ -521,7 +521,7 @@ fn test_initializer() {
     let mut state = STATE();
     Account::InternalImpl::initializer(ref state, PUBLIC_KEY);
 
-    let event = testing::pop_log::<OwnerAdded>(ZERO()).unwrap();
+    let event = utils::pop_log::<OwnerAdded>(ZERO()).unwrap();
     assert(event.new_owner_guid == PUBLIC_KEY, 'Invalid owner key');
     utils::assert_no_events_left(ZERO());
 
@@ -577,7 +577,7 @@ fn test__set_public_key() {
     let mut state = STATE();
     Account::InternalImpl::_set_public_key(ref state, PUBLIC_KEY);
 
-    let event = testing::pop_log::<OwnerAdded>(ZERO()).unwrap();
+    let event = utils::pop_log::<OwnerAdded>(ZERO()).unwrap();
     assert(event.new_owner_guid == PUBLIC_KEY, 'Invalid owner key');
     utils::assert_no_events_left(ZERO());
 
diff --git a/src/tests/token/test_erc20.cairo b/src/tests/token/test_erc20.cairo
index 6ff440859..73f4034a3 100644
--- a/src/tests/token/test_erc20.cairo
+++ b/src/tests/token/test_erc20.cairo
@@ -9,6 +9,7 @@ use openzeppelin::token::erc20::ERC20::ERC20Impl;
 use openzeppelin::token::erc20::ERC20::InternalImpl;
 use openzeppelin::token::erc20::ERC20::Transfer;
 use openzeppelin::token::erc20::ERC20;
+use openzeppelin::utils::serde::SerializedAppend;
 use starknet::ContractAddress;
 use starknet::contract_address_const;
 use starknet::testing;
@@ -597,6 +598,12 @@ fn assert_event_approval(owner: ContractAddress, spender: ContractAddress, value
     assert(event.owner == owner, 'Invalid `owner`');
     assert(event.spender == spender, 'Invalid `spender`');
     assert(event.value == value, 'Invalid `value`');
+
+    // Check indexed keys
+    let mut indexed_keys = array![];
+    indexed_keys.append_serde(owner);
+    indexed_keys.append_serde(spender);
+    utils::assert_indexed_keys(event, indexed_keys.span())
 }
 
 fn assert_only_event_approval(owner: ContractAddress, spender: ContractAddress, value: u256) {
@@ -609,6 +616,12 @@ fn assert_event_transfer(from: ContractAddress, to: ContractAddress, value: u256
     assert(event.from == from, 'Invalid `from`');
     assert(event.to == to, 'Invalid `to`');
     assert(event.value == value, 'Invalid `value`');
+
+    // Check indexed keys
+    let mut indexed_keys = array![];
+    indexed_keys.append_serde(from);
+    indexed_keys.append_serde(to);
+    utils::assert_indexed_keys(event, indexed_keys.span());
 }
 
 fn assert_only_event_transfer(from: ContractAddress, to: ContractAddress, value: u256) {
diff --git a/src/tests/token/test_erc721.cairo b/src/tests/token/test_erc721.cairo
index 4299928f9..c0eb59bea 100644
--- a/src/tests/token/test_erc721.cairo
+++ b/src/tests/token/test_erc721.cairo
@@ -20,6 +20,7 @@ use openzeppelin::token::erc721::ERC721::{
 };
 use openzeppelin::token::erc721::ERC721;
 use openzeppelin::token::erc721;
+use openzeppelin::utils::serde::SerializedAppend;
 use starknet::contract_address_const;
 use starknet::ContractAddress;
 use starknet::testing;
@@ -1389,6 +1390,12 @@ fn assert_event_approval_for_all(
     assert(event.operator == operator, 'Invalid `operator`');
     assert(event.approved == approved, 'Invalid `approved`');
     utils::assert_no_events_left(ZERO());
+
+    // Check indexed keys
+    let mut indexed_keys = array![];
+    indexed_keys.append_serde(owner);
+    indexed_keys.append_serde(operator);
+    utils::assert_indexed_keys(event, indexed_keys.span());
 }
 
 fn assert_event_approval(owner: ContractAddress, approved: ContractAddress, token_id: u256) {
@@ -1397,6 +1404,13 @@ fn assert_event_approval(owner: ContractAddress, approved: ContractAddress, toke
     assert(event.approved == approved, 'Invalid `approved`');
     assert(event.token_id == token_id, 'Invalid `token_id`');
     utils::assert_no_events_left(ZERO());
+
+    // Check indexed keys
+    let mut indexed_keys = array![];
+    indexed_keys.append_serde(owner);
+    indexed_keys.append_serde(approved);
+    indexed_keys.append_serde(token_id);
+    utils::assert_indexed_keys(event, indexed_keys.span());
 }
 
 fn assert_event_transfer(from: ContractAddress, to: ContractAddress, token_id: u256) {
@@ -1405,4 +1419,11 @@ fn assert_event_transfer(from: ContractAddress, to: ContractAddress, token_id: u
     assert(event.to == to, 'Invalid `to`');
     assert(event.token_id == token_id, 'Invalid `token_id`');
     utils::assert_no_events_left(ZERO());
+
+    // Check indexed keys
+    let mut indexed_keys = array![];
+    indexed_keys.append_serde(from);
+    indexed_keys.append_serde(to);
+    indexed_keys.append_serde(token_id);
+    utils::assert_indexed_keys(event, indexed_keys.span());
 }
diff --git a/src/tests/upgrades/test_upgradeable.cairo b/src/tests/upgrades/test_upgradeable.cairo
index c43f8518f..fff1d8ed6 100644
--- a/src/tests/upgrades/test_upgradeable.cairo
+++ b/src/tests/upgrades/test_upgradeable.cairo
@@ -10,7 +10,6 @@ use openzeppelin::upgrades::upgradeable::Upgradeable::Upgraded;
 use starknet::ClassHash;
 use starknet::ContractAddress;
 use starknet::Felt252TryIntoClassHash;
-use starknet::testing;
 
 const VALUE: felt252 = 123;
 
@@ -46,7 +45,7 @@ fn test_upgraded_event() {
     let v1 = deploy_v1();
     v1.upgrade(V2_CLASS_HASH());
 
-    let event = testing::pop_log::<Upgraded>(v1.contract_address).unwrap();
+    let event = utils::pop_log::<Upgraded>(v1.contract_address).unwrap();
     assert(event.class_hash == V2_CLASS_HASH(), 'Invalid class hash');
 }
 
diff --git a/src/tests/utils.cairo b/src/tests/utils.cairo
index e0ebeacb3..74ce5893a 100644
--- a/src/tests/utils.cairo
+++ b/src/tests/utils.cairo
@@ -18,16 +18,35 @@ fn deploy(contract_class_hash: felt252, calldata: Array<felt252>) -> ContractAdd
 
 /// Pop the earliest unpopped logged event for the contract as the requested type
 /// and checks there's no more data left on the event, preventing unaccounted params.
-/// Indexed event members are currently not supported, so they are ignored.
+/// This function also removes the first key from the event. This is because indexed
+/// params are set as event keys, but the first event key is always set as the 
+/// event ID.
 fn pop_log<T, impl TDrop: Drop<T>, impl TEvent: starknet::Event<T>>(
     address: ContractAddress
 ) -> Option<T> {
     let (mut keys, mut data) = testing::pop_log_raw(address)?;
+
+    // Remove the event ID from the keys
+    keys.pop_front();
+
     let ret = starknet::Event::deserialize(ref keys, ref data);
     assert(data.is_empty(), 'Event has extra data');
     ret
 }
 
+/// Asserts that `expected_keys` exactly matches the indexed keys from `event`.
+/// `expected_keys` must include all indexed event keys for `event` in the order
+/// that they're defined. 
+fn assert_indexed_keys<T, impl TDrop: Drop<T>, impl TEvent: starknet::Event<T>>(
+    event: T, expected_keys: Span<felt252>
+) {
+    let mut keys = array![];
+    let mut data = array![];
+
+    event.append_keys_and_data(ref keys, ref data);
+    assert(expected_keys == keys.span(), 'Invalid keys');
+}
+
 fn assert_no_events_left(address: ContractAddress) {
     assert(testing::pop_log_raw(address).is_none(), 'Events remaining on queue');
 }
diff --git a/src/token/erc20/erc20.cairo b/src/token/erc20/erc20.cairo
index c62cd3803..ee1204d36 100644
--- a/src/token/erc20/erc20.cairo
+++ b/src/token/erc20/erc20.cairo
@@ -27,14 +27,18 @@ mod ERC20 {
 
     #[derive(Drop, starknet::Event)]
     struct Transfer {
+        #[key]
         from: ContractAddress,
+        #[key]
         to: ContractAddress,
         value: u256
     }
 
     #[derive(Drop, starknet::Event)]
     struct Approval {
+        #[key]
         owner: ContractAddress,
+        #[key]
         spender: ContractAddress,
         value: u256
     }
diff --git a/src/token/erc721/erc721.cairo b/src/token/erc721/erc721.cairo
index d67952f2d..8572f50c8 100644
--- a/src/token/erc721/erc721.cairo
+++ b/src/token/erc721/erc721.cairo
@@ -37,21 +37,29 @@ mod ERC721 {
 
     #[derive(Drop, starknet::Event)]
     struct Transfer {
+        #[key]
         from: ContractAddress,
+        #[key]
         to: ContractAddress,
+        #[key]
         token_id: u256
     }
 
     #[derive(Drop, starknet::Event)]
     struct Approval {
+        #[key]
         owner: ContractAddress,
+        #[key]
         approved: ContractAddress,
+        #[key]
         token_id: u256
     }
 
     #[derive(Drop, starknet::Event)]
     struct ApprovalForAll {
+        #[key]
         owner: ContractAddress,
+        #[key]
         operator: ContractAddress,
         approved: bool
     }