Abstract: The standard notion of concordance and cobordism of smooth knots translates into a notion of Lagrangian concordance and cobordism for Legendrian knots. A natural question is then: can we interpret the cobordism relation as a sequence of moves in the front diagrams of the knots? We will look at the elementary handle attachments that yield a "decomposable" cobordism (Ekholm-Honda-Kalman). We will then construct cobordisms and concordances that are not decomposable in the EHK sense (this is a new result) and end with some currently open questions.