As their infrastructures age, utilities are increasingly challenged to maintain levels of service while keeping water affordable to all. Water main condition assessment helps utilities meet this challenge by identifying more precisely where money is best spent, leaving in place pipelines that have adequate integrity, and preventing the unnecessary failure of others. This manual provides technical information to aid utility managers and engineers in making informed decisions, along with practical information about how methods can be deployed. It covers the benefits of condition assessment, how to plan for and build a condition assessment program, methods of condition assessment, strategies for economical assessments, and how information gathered during condition assessment can be best used by utilities in managing their systems.