This paper investigates the effectiveness of several methods intending to forecast the number of yearly PCT applications at WIPO. Forecasting exercises have been applied for total PCT applications and for 5 countries accounting for more than 70 per cent of total PCT applications. So far, with the available data, the best 'fit' is obtained either with yearly data on total PCT and the AR(1) method (as opposed to country-specific estimations that have been subsequently aggregated for total PCT previsions) or with panel data estimates that include economic variables (GDP and R&D) for 5 countries. The forecasts of total PCT applications in 2002 range between 120 and 127 thousands units and between 140 and 150 thousands units in 2003. Several avenues for improvement are suggested, including an improved linearization of the basic series (other than logarithmic transformation), the use of sector specific data (as opposed to country-specific), and the use of national priority applications for the prevision of the forthcoming declining growth period (or 'stationary' period).