diff --git a/src/main/scala/ninetyNineScalaProblems/Problem07.scala b/src/main/scala/ninetyNineScalaProblems/Problem07.scala
new file mode 100644
index 0000000..17454eb
--- /dev/null
+++ b/src/main/scala/ninetyNineScalaProblems/Problem07.scala
@@ -0,0 +1,12 @@
+package ninetyNineScalaProblems
+
+import scala.annotation.tailrec
+
+object Problem07:
+    def flattenNestedList(list: List[Any]): List[Any] =
+        def loop(l: List[Any]): List[Any] = 
+            l.flatMap: 
+                case ls: List[Any] => loop(ls)
+                case e => List(e)
+
+        loop(list)
\ No newline at end of file
diff --git a/src/test/scala/ninetyNineScalaProblems/Problem07Suite.scala b/src/test/scala/ninetyNineScalaProblems/Problem07Suite.scala
new file mode 100644
index 0000000..742e643
--- /dev/null
+++ b/src/test/scala/ninetyNineScalaProblems/Problem07Suite.scala
@@ -0,0 +1,14 @@
+package ninetyNineScalaProblems
+
+class Problem07Suite extends munit.FunSuite:
+    List(
+        (List(1, List(2, 3), List(List(4))), List(1, 2, 3, 4)),
+        (List(List()),  List()),
+        (List(1, List(2, 3)),  List(1, 2, 3)),
+        (List(0, 0, 0), List(0, 0, 0)),
+        (List(1), List(1)),
+        (List(), List())
+    ).foreach:
+        case (list, expected) =>
+            test(s"flattenNestedList returns [$expected]"):
+                assertEquals(Problem07.flattenNestedList(list), expected)
\ No newline at end of file