  We present constructions and results about GDDs with two groups and block
size 6. We study those GDDs in which each block has configuration (s,t), that
is in which each block has exactly s points from one of the two groups and t
points from the other. We show the necessary conditions are sufficient for the
existence of GDD(n,2,6;{\lambda}1,{\lambda}2)s with fixed block configuration
(3,3). For configuration (1,5), we give minimal or near-minimal index examples
for all group sizes n \geq 5 except n = 10, 15, 160, or 190. For configuration
(2,4), we provide constructions for several families of
GDD(n,2,6;{\lambda}1,{\lambda}2)s.
