Adjoint functor theorems for ∞‐categories

Adjoint functor theorems give necessary and sufficient conditions for a functor to admit an adjoint. In this paper, we prove general adjoint functor theorems for functors between ∞‐categories. One of our main results is an ∞‐categorical generalization of Freyd's classical General Adjoint Functor Theorem. As an application of this result, we recover Lurie's adjoint functor theorems for presentable ∞‐categories. We also discuss the comparison between adjunctions of ∞‐categories and homotopy adjunctions, and give a treatment of Brown representability for ∞‐categories based on Heller's purely categorical formulation of the classical Brown representability theorem.