This review addresses the evolutionary and theoretical aspects of the study of life strategies in plants, from the first theoretical work of Cole to the newly developed theoretical and empirical work. The concept of vital strategy is reviewed, as well as the trade-offs between the features that define it (survival, start of reproductive maturity, number of breeding episodes, reproductive stress per episode), and a summary is made of the extensive theoretical modelling carried out so far with the aim of predicting under which conditions one strategy will be favoured over others or even under which scenarios the co-existence of alternative strategies could occur. Finally, it is disputed whether the selective forces experienced by balanced populations (majority ownership of evolutionary theories) are extended to populations that are not in a balanced state, with emphasis on populations of invasive species whose range is rapidly expanding. Variations in distribution areas can have a profound impact on the evolution of life strategies, processes that are detectable on an ecological time scale and with potential implications for biodiversity conservation.