Abstract: An integral sterile access/GMP valve housing having an integrally formed valve housing block. The housing having an inlet port, an outlet port, and a sampling port. The housing having an upstream passage extending from the inlet port. The housing having a downstream passage extending to the outlet port. The housing having a main flow weir disposed between the upstream and downstream passages. The housing having a primary passage extending from the downstream passage. The housing having a secondary passage extending to the sampling port. The valve housing having a sampling weir disposed between the primary and secondary passages. The housing is positionable in a sterile access orientation with the sampling weir and lowermost portions of the downstream and primary passages being horizontally aligned. The housing is positionable in a GMP orientation with the main flow weir and lowermost portions of the downstream and primary passages being horizontally aligned.