Abstract The impact of solar phenomena and correlated geomagnetic, ionospheric and magnetospheric activity on various technologies is indisputable. The most important element in solar-terrestrial forecasting is the understanding of solar events and their impact on the earth's environment. The problems facing forecasters of solar-terrestrial activity were discussed at the Solar-Terrestrial Predictions Workshop held in Ottawa, Canada in May 1992. The results and recommendations of the scientists participating in this Workshop are presented.