The technique of operation of the haul seine as traditionally used in the large fresh water bodies of Florida is discussed. Limiting factors inherent in the sampling device are enumerated and illustrated by seine catches from several lakes. Rotenone studies from some of these lakes are contrasted with the seine catches. The results of creel census studies in lakes extensively fished by sportsmen, by reflecting proportionate quantities of game fishes similar to quantities taken in the haul seine, are quoted as further validation for its use in qualitative population. sampling. Difficulties in quantitative sampling by this method are discussed. It is shown to be of questionable value when employed for approaching absolute terms such as productivity in pounds per acre except in certain special cases. The value of the haul seine for purely relative comparisons is emphasized.