This document provides information about cerebrospinal fluid (CSF) and other body fluids analyzed for diagnostic purposes. It discusses the typical volumes and functions of CSF in adults and children. Methods for CSF specimen collection including cisternal and ventricular puncture are described. The document outlines the gross examination, biochemical analysis, and cell counts performed on CSF. Key findings in bacterial, viral, fungal and tuberculous meningitis from lumbar puncture are also summarized. Information on synovial fluid, lymph, and their analysis is also provided.