The NPDES Permit Writers’ Manual (EPA-833-K-10-001) provides a comprehensive overview of the framework of the NPDES program and serves as one of the principal training tools to help permit writers develop legally defensible and enforceable NPDES permits. Its primary purpose as a technical resource is to guide new state and EPA permit writers through the basic steps of permit development and issuance; however, the manual also is intended to serve as a resource for others (e.g., stakeholders, the regulated community) interested in the NPDES permitting process.