Sentence:  Churches can be strengthened through this process of co-optation so long as the environs of the church provide a sufficient pool of people who can fit the pattern of economic <WSD>integration</WSD> ; once the pool of recruits diminishes , the congregation is helpless - friendly contacts no longer keep it going . 
Meaning of the word marked with <WSD> tags:  the action of incorporating a racial or religious group into a community