This Manual of Practice summarizes and presents these practices so that they can be more uniformly used by wastewater professionals. An overview of membrane and biological process fundamentals as they apply to MBRs is first provided and these fundamental principles then support information on the integrated process design of MBR systems. The physical design of features unique to MBRs is addressed and approaches for the procurement of membrane equipment are summarized. Finally, this manual covers the operation of properly designed MBR facilities Changes to new edition: Address changes and revisions based on comments solicited via industry-professional review Amend information to reflect lessons-learnt and current best-practices as developed in the decade since this manual was first published Include information and design principles for new and emerging applications.