diff --git a/navMesh/walk/NavMeshWalkParams.h b/navMesh/walk/NavMeshWalkParams.h
index b569fbc..4a89d87 100644
--- a/navMesh/walk/NavMeshWalkParams.h
+++ b/navMesh/walk/NavMeshWalkParams.h
@@ -64,6 +64,10 @@ namespace NM {
 			return _toBeWalkedDistance;
 		}
 
+		void check() const {
+			Assert::isFalse(numSteps == 0, "num Steps = 0 is currently not supported. must be >= 1");
+		}
+
 	private:
 
 		// precalc
diff --git a/navMesh/walk/NavMeshWalkRandom.h b/navMesh/walk/NavMeshWalkRandom.h
index 083db2c..8adff15 100644
--- a/navMesh/walk/NavMeshWalkRandom.h
+++ b/navMesh/walk/NavMeshWalkRandom.h
@@ -50,6 +50,9 @@ namespace NM {
 
 		ResultEntry getOne(const NavMeshWalkParams<Tria>& params) const {
 
+			// sanity checks
+			params.check();
+
 			ResultEntry res;
 			res.probability = 0;
 
@@ -94,6 +97,9 @@ namespace NM {
 
 		ResultList getMany(const NavMeshWalkParams<Tria>& params) const {
 
+			// sanity checks
+			params.check();
+
 			ResultList res;
 
 			// to-be-walked distance;
diff --git a/navMesh/walk/NavMeshWalkSemiDirected.h b/navMesh/walk/NavMeshWalkSemiDirected.h
index 27c35bd..2eb661e 100644
--- a/navMesh/walk/NavMeshWalkSemiDirected.h
+++ b/navMesh/walk/NavMeshWalkSemiDirected.h
@@ -50,6 +50,9 @@ namespace NM {
 
 		ResultEntry getOne(const NavMeshWalkParams<Tria>& params) {
 
+			// sanity checks
+			params.check();
+
 			ResultEntry re;
 
 			static Distribution::Uniform<float> dHead(-0.10, +0.10, 1337);
@@ -117,7 +120,12 @@ namespace NM {
 		}
 
 		ResultList getMany(const NavMeshWalkParams<Tria>& params) {
+
+			// sanity checks
+			params.check();
+
 			return {getOne(params)};
+
 		}
 
 
diff --git a/navMesh/walk/NavMeshWalkSemiRandom.h b/navMesh/walk/NavMeshWalkSemiRandom.h
index f4b95c6..fff38ec 100644
--- a/navMesh/walk/NavMeshWalkSemiRandom.h
+++ b/navMesh/walk/NavMeshWalkSemiRandom.h
@@ -53,6 +53,9 @@ namespace NM {
 
 		ResultEntry getOne(const NavMeshWalkParams<Tria>& params) const {
 
+			// sanity checks
+			params.check();
+
 			static Distribution::Normal<float> dDist(1.0, 0.4);
 			static Distribution::Normal<float> dHead(0.0, 1.0);
 
@@ -106,6 +109,9 @@ namespace NM {
 
 		ResultList getMany(const NavMeshWalkParams<Tria>& params) const {
 
+			// sanity checks
+			params.check();
+
 			static Distribution::Normal<float> dDist(1.0, 0.4);
 			static Distribution::Normal<float> dHead(0.0, 1.0);
 
diff --git a/navMesh/walk/NavMeshWalkSimple.h b/navMesh/walk/NavMeshWalkSimple.h
index 4184ba0..7819b41 100644
--- a/navMesh/walk/NavMeshWalkSimple.h
+++ b/navMesh/walk/NavMeshWalkSimple.h
@@ -52,6 +52,9 @@ namespace NM {
 
 		ResultEntry getOne(const NavMeshWalkParams<Tria>& params) {
 
+			// sanity checks
+			params.check();
+
 			ResultEntry re;
 
 			// to-be-walked distance;
@@ -103,7 +106,12 @@ namespace NM {
 		}
 
 		ResultList getMany(const NavMeshWalkParams<Tria>& params) {
+
+			// sanity checks
+			params.check();
+
 			return {getOne(params)};
+
 		}