The responsibilities of the USDA under the Packers and Stockyards Act (PSA) for monitoring the cattle and hog industries, and halting unfair and anticompetitive practices (AP) in the marketing of cattle and hogs, are assigned to the Grain Insp., Packers and Stockyards Admin. (GIPSA). This report discusses: the no. and status of investigations conducted by GIPSA in response to complaints and concerns about anticompetitive activity involving the marketing of cattle and hogs; and factors that affect GIPSA's ability to investigate concerns about AP. Contains info. on GIPSA's authority to address concerns about AP and unfair practices in the cattle and hog markets.