Seven life-history traits were used to describe the life-history strategies of 12 native and introduced species from a permanent lake in Spain. Multivariate analysis identified a continuum of life-history patterns between two extremes: 1) species with one or few spawnings per year, short breeding season, long generation time, large size, high fecundity, and no parental care. This set of life-history traits corresponded to the periodic life-history strategy described by Winemiller (1989) and Winemiller and Rose (1992); and 2) species with multiple spawnings per year, prolonged breeding season, short generation time, small size, low fecundity, parental care, and small to medium size of eggs. This association of life-history traits corresponded to the opportunistic life-history strategy described by Winemiller (1989) and Winemiller and Rose (1992). It seems that there were no apparent differences in life-history strategies between native and introduced species in Lake Banyoles. Native and introduced species were found among periodic and opportunistic strategists. Observed differences in the success of native and introduced species with comparable life-history strategies seems to suggest that the success of fish species in Lake Banyoles could not be explained on the basis of life-history features. Nevertheless, it seems that successful invasive species in Lake Banyoles display a suite of traits such as high fecundity, late maturity, and large body size. These characteristics may perhaps be viewed as biological predictors of successful invaders but more information is needed about life-history features of successful introduced species from other ecosystems.