Active clearance control system and method for a gas turbine engine

A method (100) and system (26) to provide clearance control for a gas turbine having a multi-stage compressor and a turbine having turbine buckets rotating within a turbine shell, the method includes: selecting (102) a first compressor stage from which to extract compressed air; ducting the compressed air from the first compressor stage to the turbine shell; passing (106) the compressed air from the first compressor stage to thermally contract the turbine shell; selecting a second compressor stage (102) from which to extract compressed air and deselecting the first compressor stage; ducting the compressed air from the second compressor stage to the turbine shell, and passing (106) the compressed air from the second compressor stage to thermal expand the turbine shell.