The models of root system development that emerged in the early 1970s were based on root length density distribution, but the last decade has seen the development of more sophisticated architectural models and computer-intensive techniques. In this presentation, I will make the case for more widespread use of simpler models of root systems based on continuous descriptions of their structure. A new theoretical framework will be presented that describes the dynamics of root density distributions as a function of individual root developmental parameters such as rates of lateral root initiation, elongation, mortality, and gravitropism. Continuous root architectural models could have a wide range of applications, particularly for individual based population models where standard architectural models show some limitations. I will present examples of plant/plant interactions scenarios to illustrate potential applications for continuous root architectural models.