Farm management research in developing countries originally focused on the collection and analysis of input-output type data obtained by survey methods for the purpose of improving resource allocation of individual farmers. More recently, with the belief that this has not been a cost effective approach for developing countries, farm management research has broadened its objectives to provide information to provide a stronger foundation micro-level data that may be used for policy analysis and decision-making. Some modifications of farm management research have been made to fit the situation in developing countries, usually by using more reliable (and more costly) methods, such as frequent visits for field measurement, for obtaining input-output data. The multiple visit method uses carefully designed interview schedules to be administered in repeated visits to participant households during a month and extending over a relevant period, such as a crop season or calendar year. The advantage of the multiple visit approach over other survey types is that less reliance is placed on a respondents ability to remember distant events. Two factors are critical in the design of a survey using the multiple visits method which affect the cost of collecting, processing and using information as well as its reliability. The first objective of this study is to describe the Mandara Area Development Project in Cameroon where these two methods (bi-weekly and one-shot survey) are used to collect input-output data at the farm level. The second objective will be an empirical assessment of the accepted views concerning the one-shot survey and the weekly or bi-weekly visits. Data collected from the Mandara Area Development Project in 1980 will be used. Labor and other input data were gathered by one-shot survey on a recall basis for specific crop enterprises for previous growing season. Labor data and other input data were collected on a bi-weekly basis for two crop and one animal enterprise currently operating on each farm. The third objective will be to prescribe, based upon the results of the study and empirical evidence from other studies, recommendations for collecting input-output farm data for economic planning and decision making for the developing countries, particularly for the African ones.