Part 1. Ways to use the organ creatively in worship (a mini-course in improvising on hymntunes) -- Modulations to the doxology (old hundredth) -- Five harmonizations of the doxology -- Twenty-one ways to improvise on the hymntunes for the organ -- Ways to improvise interludes and codas -- Part 2. The creative use of the organ in worship (organ setting possibilities for 254 hymntunes).