A system for a gas turbine engine, comprising: a manifold configured to be secured on the gas turbine engine, the manifold being a single, unitary thermal management system manifold, the manifold including: a plurality of interfaces, including: a first interface which is fuel/engine oil cooler interface; a second interface which is a fuel/generator oil cooler interface; a third interface which is a generator oil/engine oil cooler interface; and a fourth interface which is a return-to-tank interface; the system further comprising: a fuel/engine oil cooler mounted directly to the fuel/engine oil cooler interface in the manifold; a fuel/generator oil cooler mounted directly to the fuel/generator oil cooler interface in the manifold; a generator oil/engine oil cooler mounted directly to the generator oil/engine oil cooler interface in the manifold; and a return-to-tank valve mounted directly to the return-to-tank interface in the manifold; wherein the thermal management system manifold includes a plurality of passages for delivering fluid between the plurality of interfaces, including: a first passage fluidly connecting the generator oil/engine oil cooler interface and the fuel/generator oil cooler interface; a second passage fluidly connecting the fuel/generator oil cooler interface and the fuel/engine oil cooler interface; and wherein the manifold further includes: a third passage for carrying fuel into the return-to-tank valve; and a fourth passage fluidly connected to the fuel/engine oil cooler interface for carrying cooled generator oil from the fuel/generator oil cooler to a generator located outside of the thermal management system manifold. a plurality of interfaces, including: a first interface which is fuel/engine oil cooler interface; a second interface which is a fuel/generator oil cooler interface; a third interface which is a generator oil/engine oil cooler interface; and a fourth interface which is a return-to-tank interface; a first interface which is fuel/engine oil cooler interface; a second interface which is a fuel/generator oil cooler interface; a third interface which is a generator oil/engine oil cooler interface; and a fourth interface which is a return-to-tank interface; the system further comprising: a fuel/engine oil cooler mounted directly to the fuel/engine oil cooler interface in the manifold; a fuel/generator oil cooler mounted directly to the fuel/generator oil cooler interface in the manifold; a generator oil/engine oil cooler mounted directly to the generator oil/engine oil cooler interface in the manifold; and a return-to-tank valve mounted directly to the return-to-tank interface in the manifold; wherein the thermal management system manifold includes a plurality of passages for delivering fluid between the plurality of interfaces, including: a first passage fluidly connecting the generator oil/engine oil cooler interface and the fuel/generator oil cooler interface; a second passage fluidly connecting the fuel/generator oil cooler interface and the fuel/engine oil cooler interface; and wherein the manifold further includes: a third passage for carrying fuel into the return-to-tank valve; and a fourth passage fluidly connected to the fuel/engine oil cooler interface for carrying cooled generator oil from the fuel/generator oil cooler to a generator located outside of the thermal management system manifold. a fuel/engine oil cooler mounted directly to the fuel/engine oil cooler interface in the manifold; a fuel/generator oil cooler mounted directly to the fuel/generator oil cooler interface in the manifold; a generator oil/engine oil cooler mounted directly to the generator oil/engine oil cooler interface in the manifold; and a return-to-tank valve mounted directly to the return-to-tank interface in the manifold; wherein the thermal management system manifold includes a plurality of passages for delivering fluid between the plurality of interfaces, including: a first passage fluidly connecting the generator oil/engine oil cooler interface and the fuel/generator oil cooler interface; a second passage fluidly connecting the fuel/generator oil cooler interface and the fuel/engine oil cooler interface; and wherein the manifold further includes: a third passage for carrying fuel into the return-to-tank valve; and a fourth passage fluidly connected to the fuel/engine oil cooler interface for carrying cooled generator oil from the fuel/generator oil cooler to a generator located outside of the thermal management system manifold. a first passage fluidly connecting the generator oil/engine oil cooler interface and the fuel/generator oil cooler interface; a second passage fluidly connecting the fuel/generator oil cooler interface and the fuel/engine oil cooler interface; and wherein the manifold further includes: a third passage for carrying fuel into the return-to-tank valve; and a fourth passage fluidly connected to the fuel/engine oil cooler interface for carrying cooled generator oil from the fuel/generator oil cooler to a generator located outside of the thermal management system manifold. a third passage for carrying fuel into the return-to-tank valve; and a fourth passage fluidly connected to the fuel/engine oil cooler interface for carrying cooled generator oil from the fuel/generator oil cooler to a generator located outside of the thermal management system manifold.