World fishery landing statistics as disseminated by FAO have been completely revised for the period 1950-1969 and time series in the database have been extended back 20 years so that the period covered is now 1950-1994. Through a preliminary analysis of trends, globally and by oceans, we attempt to demonstrate that these extended time series can be very useful in interpreting developments in the worlds fisheries and so help in assessing the present situation as well as for planning and policy-making for the future. Grouping the 200 most important resources into a few categories according to the shapes of their landings trends reveals a variety of patterns which seem to form different segments of a generalized fishery development model comprising undeveloped, developing, mature and senescent phases. The analysis demonstrates strikingly the succession of the passage of the majority of the worlds major resources through these phases, indicating the current general saturation of fisheries development and increasing overexploitation. Fisheries potential was estimated by predicting at which point the relative rate of increase of landings is zero, using the same generalized fishery development model applied to total fishery production data for marine fish and shellfish. The analysis was applied using data aggregated to three different levels: a total for all oceans; totals for each ocean; and individual FAO major fishing areas. Estimated fishery potential for the worlds oceans increases as the level of aggregation of the data decreases and the results indicate that marine fishery potential may be higher than has been assumed up to now. The areas and resources which might provide potential increases in production are identified.