This paper examines various aspects of the recently proposed theory of coincident membranes by Bagger and Lambert. These include the properties of open membranes and the resulting boundary theory with an interpretation in terms of the fivebrane and marginal supersymmetric deformations of the interactions with the relation to the holographic dual.

Using the techniques developed by Lunin and Maldacena we calaculate the supergravity solutions of membranes and fivebranes in the presence of a background C field. All the distinct possible C-field configurations are explored.Decoupling limits for these branes are then described that preserve the deformation leading to families of M-theory brane deformation duals. The decoupled geometry is then explored using probe brane techniques and brane thermodynamics.