"The National Institute of Agricultural and Food Research and Technology (INIA) started in 1966 a research program for the introduction of exotic conifers, with the main objective of increasing timber production. This research followed similar programs in most of the European forestry research centres during the middle of the XX century. The Spanish network was established using material from 42 conifers, planted in 87 sites in order to evaluate the production and adaptation under different contrasting ecological conditions. The network was evaluated (survival, height and diameter growth) up to 1982. This monograph presents the main results obtained during the experimental period. For each tested species, we include a summary of the morphology, ecology, silviculture, yield and production in the natural distribution area, and the performance in sites of the Spanish network. For each experimental site, we include a summary of the main results for each material tested. The production and adaptation has been evaluated by different traits as survival, height and diameter increments. These variables, however, have been affected by the lack of silvicultural treatments during the evaluation period. The present monograph, based on a large number of species tested under a wide range of ecological conditions, would complement the results obtained for some of the species in other European countries."--Summary.