This chapter discusses urine analysis, where urine should be collected in clean and if necessary sterile containers. An early morning fasting specimen is the most concentrated one and preferred for most examinations. Pathological conditions such as diabetes mellitus, diabetes insipidus and chronic nephritis are associated with an increased volume of urine. In acute nephritis, diseases of heart and lungs, fever, diarrhea and vomiting, urine volume decreases. Normal urine ordinarily possesses an amber yellow tint, the depth of the color being dependent in part upon the density of the fluid. The odor of normal urine is of a faint, aromatic type. The reactions of the urine represent equilibrium among a large number of acidic and basic constituents, both organic and inorganic which it contains. Bile salts and bile pigments are absent in normal urine. The pathological condition in which blood occurs in the urine may be classified under two divisions, hematuria and hemoglobinuria.