diff --git a/gtsam/inference/BayesNet.h b/gtsam/inference/BayesNet.h
index a05440d69..0f78a15e3 100644
--- a/gtsam/inference/BayesNet.h
+++ b/gtsam/inference/BayesNet.h
@@ -81,7 +81,7 @@ public:
   }
 
   /** BayesNet with 1 conditional */
-  BayesNet(const sharedConditional& conditional) { push_back(conditional); }
+  explicit BayesNet(const sharedConditional& conditional) { push_back(conditional); }
 
 	/// @}
 	/// @name Testable
diff --git a/gtsam/inference/BayesTree.h b/gtsam/inference/BayesTree.h
index 06a47ba8e..9cba86267 100644
--- a/gtsam/inference/BayesTree.h
+++ b/gtsam/inference/BayesTree.h
@@ -144,7 +144,7 @@ namespace gtsam {
 		BayesTree() {}
 
 		/** Create a Bayes Tree from a Bayes Net (requires CONDITIONAL is IndexConditional *or* CONDITIONAL::Combine) */
-		BayesTree(const BayesNet<CONDITIONAL>& bayesNet);
+		explicit BayesTree(const BayesNet<CONDITIONAL>& bayesNet);
 
 		/// @}
 		/// @name Advanced Constructors