diff --git a/GTSAM-Concepts.md b/GTSAM-Concepts.md
index ef16a2c5d..0fd55932e 100644
--- a/GTSAM-Concepts.md
+++ b/GTSAM-Concepts.md
@@ -107,7 +107,7 @@ Hence, we have the following extra valid expressions:
 
 where above the `H` arguments stand for optional Jacobian arguments. 
 That makes it possible to create factors implementing priors (PriorFactor) or relations between 
-two instances of a Lie group type (BteweenFactor).
+two instances of a Lie group type (BetweenFactor).
 
 Lie Group Action
 ----------------