diff --git a/include/MathFramework.h b/include/MathFramework.h
index 96e18c2..6ecdea1 100644
--- a/include/MathFramework.h
+++ b/include/MathFramework.h
@@ -22,4 +22,18 @@
  */
 bool att(const TaskInstance& writerTask, const TaskInstance& readerTask);
 
+/**
+ * @brief Determines if the writer and reader tasks overlap in execution.
+ * 
+ * The more important “critical function” crit determines if
+ * (even in case of non-activation time travel) writer and reader
+ * overlap in execution:
+ * 
+ * @param writerTask The task instance representing the writer.
+ * @param readerTask The task instance representing the reader.
+ * @return true if there is an overlap in execution between writer and reader.
+ * @return false if there is no overlap in execution.
+ */
+bool crit(const TaskInstance& writerTask, const TaskInstance& readerTask);
+
 #endif
\ No newline at end of file
diff --git a/source/MathFramework.cpp b/source/MathFramework.cpp
index d54c2e8..7500a39 100644
--- a/source/MathFramework.cpp
+++ b/source/MathFramework.cpp
@@ -7,3 +7,13 @@ bool att(const TaskInstance& writerTask, const TaskInstance& readerTask) {
 
     return false;
 }
+
+bool crit(const TaskInstance& writerTask, const TaskInstance& readerTask) {
+    int writerTaskTerminationTime = writerTask.activationTime + writerTask.wcet;
+
+    if(readerTask.activationTime < writerTaskTerminationTime) {
+        return true;
+    }
+
+    return false;
+}
diff --git a/tests/MathFrameworkTests.cpp b/tests/MathFrameworkTests.cpp
index 0d068cb..5829776 100644
--- a/tests/MathFrameworkTests.cpp
+++ b/tests/MathFrameworkTests.cpp
@@ -18,5 +18,25 @@ TEST(MathFramework, CanDetectWhenThereIsNoTimeTravel) {
     bool expected = false;
     bool actual = att(writerTask, readerTask);
 
+    EXPECT_EQ(expected, actual);
+}
+
+TEST(MathFramework, CritFunctionCanDetectExecutionOverlap) {
+    const TaskInstance writerTask(10, 5);
+    const TaskInstance readerTask(12, 5);
+
+    bool expected = true;
+    bool actual = crit(writerTask, readerTask);
+
+    EXPECT_EQ(expected, actual);
+}
+
+TEST(MathFramework, CritFunctionCanDetectWhenThereIsNoExecutionOverlap) {
+    const TaskInstance writerTask(10, 5);
+    const TaskInstance readerTask(16, 5);
+
+    bool expected = false;
+    bool actual = crit(writerTask, readerTask);
+
     EXPECT_EQ(expected, actual);
 }
\ No newline at end of file