R is an environment and functional programming language for statistical data analysis and visualization. Largely unknown to the functional programming community, it is popular and influential in many empirical sciences. Due to its integrated combination of dynamic and reflective scripting on one hand, and array-based numerical computation on the other, R poses unique and challenging implementation problems, at odds with the conservative language technology employed by its developers. We discuss the background of R in historical context, highlight some of the more problematic language features, and discuss the potential for the effective use of state-of-the-art language technology in a future, safe and efficient implementation.