The effectiveness of various chemical and biological compounds in controlling the odors of anaerobically stored liquid manure was measured. The criteria for acceptable odor control were consistently concurrent reduction in odor panel ratings and sulfide concentrations. Investigations of prospective odor control materials were carried out on two levels: 1) short term, which examined oxidants and an adsorbent for odor control effectiveness during 24 hour or less, and 2) long term, which examined available proprietary compounds which might exert odor control over a period of months. Short term experiments indicated that H202, NaOCl, ClO2 and KMnO4, at 500 mg/l dosage or greater, reduced sulfide (S=) and odor to acceptable level in liquid swine waste. However, activated carbon at 2,000 or 5,000 mg/l dosage did not reduce odors to acceptable levels. Long term experiments showed that dried enzymes, dried bacteria, orthodicholorobenzene containing materials and lime, were not effective in reducing the odor or S= levels of swine waste. NH4NO3 and NaNO3 were found to change the character of odor, reduce S= level and cause suspended solids to float.