RinRuby is a Ruby library that integrates the R interpreter in Ruby, making R's statistical routines and graphics available within Ruby. The library consists of a single Ruby script that is simple to install and does not require any special compilation or installation of R. Since the library is 100% pure Ruby, it works on a variety of operating systems, Ruby implementations, and versions of R. RinRuby's methods are simple, making for readable code. The {website [rinruby.ddahl.org]}[http://rinruby.ddahl.org] describes RinRuby usage, provides comprehensive documentation, gives several examples, and discusses RinRuby's implementation.