I will talk about deformations of coisotropic submanifolds in symplectic geometry. Unlike the deformation problem of Lagrangian submanifolds, the coisotropic deformation problem is generally obstructed, meaning that there may exist first order deformations which are not tangent to any path of deformations. I will review this fact and explain why the coisotropic deformation problem becomes unobstructed if one additionally keeps the diffeomorphism type of the characteristic foliation fixed.