A method comprising: running a lower completion assembly into a well in a single trip, the lower completion assembly comprising a screen , a first valve and a second valve ; performing a gravel packing operation using the assembly, the performing comprising running a service assembly into the lower completion assembly to operate the first valve ; removing the service assembly from the well ; and subsequently installing an upper completion assembly in the well , the installing comprising enabling remote control of the second valve to regulate production of fluid from the well , characterized by : performing the gravel packing operation after the running of the lower completion assembly into the well ; the performing further comprising communicating a gravel packing slurry and running the service assembly into the lower completion assembly to operate the first valve to communicate fluid from the gravel packing slurry into a central passageway of the lower completion assembly ; running an isolation seal assembly into the lower completion assembly to prevent leakage from occurring through the first valve after a gravel packing operation; and running a shifting tool at the lower end of the isolation seal assembly into the lower completion assembly to open the second valve . running a lower completion assembly into a well in a single trip, the lower completion assembly comprising a screen , a first valve and a second valve ; performing a gravel packing operation using the assembly, the performing comprising running a service assembly into the lower completion assembly to operate the first valve ; removing the service assembly from the well ; and subsequently installing an upper completion assembly in the well , the installing comprising enabling remote control of the second valve to regulate production of fluid from the well , characterized by : performing the gravel packing operation after the running of the lower completion assembly into the well ; the performing further comprising communicating a gravel packing slurry and running the service assembly into the lower completion assembly to operate the first valve to communicate fluid from the gravel packing slurry into a central passageway of the lower completion assembly ; running an isolation seal assembly into the lower completion assembly to prevent leakage from occurring through the first valve after a gravel packing operation; and running a shifting tool at the lower end of the isolation seal assembly into the lower completion assembly to open the second valve . performing the gravel packing operation after the running of the lower completion assembly into the well ; the performing further comprising communicating a gravel packing slurry and running the service assembly into the lower completion assembly to operate the first valve to communicate fluid from the gravel packing slurry into a central passageway of the lower completion assembly ; running an isolation seal assembly into the lower completion assembly to prevent leakage from occurring through the first valve after a gravel packing operation; and running a shifting tool at the lower end of the isolation seal assembly into the lower completion assembly to open the second valve . <EOS>