This study evaluated the relationship between attending to task and speed of task completion in a vocational training program. Six mentally retarded male adults were randomly assigned to 2 experimental groups and treated in multiple-baseline fashion. Group 1 received reinforcement for speed of task completion; Group 2 received reinforcement for time spent attending to task. Results showed that subjects who spent more time completing tasks also spent an appreciable percentage of their time attending to task, by comparision with baseline measures. Also, subjects reinforced for not attending to task without exception did not complete tasks. On the other hand, directly reinforcing speed of task completion resulted in speedier completion of tasks and increased time spent attending to task. Further, directly reinforcing time spent attending to task resulted in more attending and more rapid task completion. Determining which measure, when treated, would be the more economical to address was only conservatively estimated. It was suggested that reinforcing facilitative responses may reduce observed variability in responding associated with speed of task completion.