This document discusses fluid-structure interactions (FSI) involving moving boundaries, and optimization and control problems governed by FSI models. It presents the governing PDE models coupling the incompressible Navier-Stokes equations for the fluid with nonlinear elasticity equations for the structure. It discusses challenges in analyzing well-posedness and deriving first-order necessary optimality conditions due to the moving boundary and nonlinear coupling between the fluid and structure domains. The goal is to characterize optimal controls by computing the gradient of cost functionals involving the state variables and moving fluid domain.