The present disclosure relates to combustor configurations, panels and components for a gas turbine engine. In one embodiment, a combustor for a gas turbine engine includes a support structure including a plurality of openings and a plurality of panels mounted to the structure. The plurality of panels define a combustion cavity of the combustor. Each panel includes a first wall configured to receive cooling air and a second wall configured to provide air flow for the cavity. The first and second walls form a cavity and include one or more elements for controlling the cooling effectiveness of each panel. Another embodiment is directed to a combustor panel including one or more elements for controlling cooling effectiveness. Another embodiment is directed to a support structure for a combustor of a gas turbine engine. Another embodiment is directed to configurations of panels including single walled portions or single walled panels.