diff --git a/CHANGELOG.md b/CHANGELOG.md
index 46d8669..db74888 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ### Added
 
 - Reset input when escape key is pressed
+- Implement audit logging
 
 ## [0.26.6] - 2024-06-10
 
diff --git a/lib/AuditTrait.php b/lib/AuditTrait.php
new file mode 100644
index 0000000..d48a8ad
--- /dev/null
+++ b/lib/AuditTrait.php
@@ -0,0 +1,83 @@
+<?php
+
+namespace OCA\Money;
+
+use JsonSerializable;
+
+use OCP\EventDispatcher\IEventDispatcher;
+use OCP\Log\Audit\CriticalActionPerformedEvent;
+use OCP\AppFramework\Db\Entity;
+
+trait AuditTrait {
+
+  private IEventDispatcher $dispatcher;
+
+  private function emitCreateAuditEvent(string $userId, string $entityName, Entity $entity) {
+    $this->emitAuditEvent('user \'%s\' created a %s: %s', [
+      $userId,
+      $entityName,
+      json_encode($entity)
+    ]);
+  }
+
+  private function emitUpdateAuditEvents(
+    string $userId,
+    string $entityName,
+    Entity $newEntity,
+    Entity $oldEntity
+  ) {
+    $lines = $this->getLogLinesForEntityChanges(
+      $newEntity->jsonSerialize(),
+      $oldEntity->jsonSerialize()
+    );
+
+    foreach($lines as $line) {
+      $this->emitAuditEvent('user \'%s\' ' . $line . ' of %s with id %s', [
+        $userId,
+        $entityName,
+        $newEntity->id
+      ]);
+    }
+  }
+
+  private function emitDeleteAuditEvent(string $userId, string $entityName, Entity $entity) {
+    $this->emitAuditEvent('user \'%s\' deleted %s: %s', [
+      $userId,
+      $entityName,
+      json_encode($entity)
+    ]);
+  }
+
+  private function emitAuditEvent(string $message, array $params) {
+    $event = new CriticalActionPerformedEvent(
+        $message,
+        $params
+    );
+
+    $this->getDispatcher()->dispatchTyped($event);
+  }
+
+  private function getLogLinesForEntityChanges(array $newEntity, array $oldEntity) {
+    $changes = array_diff(
+      $newEntity,
+      $oldEntity
+    );
+
+    $lines = [];
+
+    foreach($changes as $key => $value) {
+      array_push($lines, 'changed ' . $key . ' from ' . $oldEntity[$key] . ' to ' . $value);
+    }
+
+    return $lines;
+  }
+
+  private function getDispatcher(): IEventDispatcher {
+    if(!isset($this->dispatcher)) {
+      $this->dispatcher = \OCP\Server::get(IEventDispatcher::class);
+    }
+
+    return $this->dispatcher;
+  }
+
+}
diff --git a/lib/Service/AccountService.php b/lib/Service/AccountService.php
index 4f4e3b1..9fa92e1 100755
--- a/lib/Service/AccountService.php
+++ b/lib/Service/AccountService.php
@@ -10,8 +10,12 @@
 use OCA\Money\Db\Account;
 use OCA\Money\Db\AccountMapper;
 
+use OCA\Money\AuditTrait;
+
 class AccountService {
 
+  use AuditTrait;
+
   private $mapper;
 
   public function __construct(AccountMapper $mapper) {
@@ -58,7 +62,11 @@ public function create(
     $account->setUserId($userId);
     $account->setBookId($bookId);
 
-    return $this->mapper->insert($account);
+    $insertedAccount = $this->mapper->insert($account);
+
+    $this->emitCreateAuditEvent($userId, 'account', $insertedAccount);
+
+    return $insertedAccount;
   }
 
   public function update(
@@ -73,6 +81,7 @@ public function update(
   ) {
     try {
       $account = $this->mapper->find($id, $userId);
+      $originalAccount = clone $account;
 
       $account->setBookId($bookId);
 
@@ -82,7 +91,11 @@ public function update(
       $account->setDescription($description);
       $account->setExtraData($extraData);
 
-      return $this->mapper->update($account);
+      $updatedAccount = $this->mapper->update($account);
+
+      $this->emitUpdateAuditEvents($userId, 'account', $updatedAccount, $originalAccount);
+
+      return $updatedAccount;
     } catch(Exception $e) {
       $this->handleException($e);
     }
@@ -92,6 +105,9 @@ public function delete($id, $userId) {
     try {
       $account = $this->mapper->find($id, $userId);
       $this->mapper->delete($account);
+
+      $this->emitDeleteAuditEvent($userId, 'account', $account);
+
       return $account;
     } catch(Exception $e) {
       $this->handleException($e);
diff --git a/lib/Service/SplitService.php b/lib/Service/SplitService.php
index f3b8ee0..a6cb7b0 100755
--- a/lib/Service/SplitService.php
+++ b/lib/Service/SplitService.php
@@ -10,8 +10,12 @@
 use OCA\Money\Db\Split;
 use OCA\Money\Db\SplitMapper;
 
+use OCA\Money\AuditTrait;
+
 class SplitService {
 
+  use AuditTrait;
+
   private $splitMapper;
 
   public function __construct(SplitMapper $splitMapper) {
@@ -57,12 +61,17 @@ public function create($transactionId, $destAccountId, $value, $convertRate, $de
     $split->setConvertRate($convertRate);
     $split->setValue($value);
 
-    return $this->splitMapper->insert($split);
+    $insertedSplit = $this->splitMapper->insert($split);
+
+    $this->emitCreateAuditEvent($userId, 'split', $insertedSplit);
+
+    return $insertedSplit;
   }
 
   public function update($id, $transactionId, $destAccountId, $value, $convertRate, $description, $userId) {
     try {
       $split = $this->splitMapper->find($id, $userId);
+      $originalSplit = clone $split;
 
       $split->setDescription($description);
       $split->setTransactionId($transactionId);
@@ -70,7 +79,11 @@ public function update($id, $transactionId, $destAccountId, $value, $convertRate
       $split->setConvertRate($convertRate);
       $split->setValue($value);
 
-      return $this->splitMapper->update($split);
+      $updatedSplit = $this->splitMapper->update($split);
+
+      $this->emitUpdateAuditEvents($userId, 'split', $updatedSplit, $originalSplit);
+
+      return $updatedSplit;
     } catch(Exception $e) {
       $this->handleException($e);
     }
@@ -80,6 +93,9 @@ public function delete($id, $userId) {
     try {
       $split = $this->splitMapper->find($id, $userId);
       $this->splitMapper->delete($split);
+
+      $this->emitDeleteAuditEvent($userId, 'split', $split);
+
       return $split;
     } catch(Exception $e) {
       $this->handleException($e);
diff --git a/lib/Service/TransactionService.php b/lib/Service/TransactionService.php
index 3a6be20..59fc32a 100644
--- a/lib/Service/TransactionService.php
+++ b/lib/Service/TransactionService.php
@@ -10,8 +10,12 @@
 use OCA\Money\Db\Transaction;
 use OCA\Money\Db\TransactionMapper;
 
+use OCA\Money\AuditTrait;
+
 class TransactionService {
 
+  use AuditTrait;
+
   private $transactionMapper;
 
   public function __construct(TransactionMapper $transactionMapper) {
@@ -63,17 +67,27 @@ public function create($description, $date, $userId) {
     $transaction->setDate($date);
     $transaction->setTimestampAdded(time());
 
-    return $this->transactionMapper->insert($transaction);
+
+    $insertedTransaction = $this->transactionMapper->insert($transaction);
+
+    $this->emitCreateAuditEvent($userId, 'transaction', $insertedTransaction);
+
+    return $insertedTransaction;
   }
 
   public function update($id, $description, $date, $userId) {
     try {
       $transaction = $this->transactionMapper->find($id, $userId);
+      $originalTransaction = clone $transaction;
 
       $transaction->setDescription($description);
       $transaction->setDate($date);
 
-      return $this->transactionMapper->update($transaction);
+      $updatedTransaction = $this->transactionMapper->update($transaction);
+
+      $this->emitUpdateAuditEvents($userId, 'transaction', $updatedTransaction, $originalTransaction);
+
+      return $updatedTransaction;
     } catch(Exception $e) {
       $this->handleException($e);
     }