Research on coercion in addiction treatment typically investigates objective sources of social pressure among legally mandated clients. Little research has examined the impact of clients' perceptions of social pressures in generalist addiction services. Clients seeking substance abuse treatment (N=300; 221 males and 79 females; M age=36.6 years) rated the extent to which treatment was being sought because of coercive social pressures (external motivation; alpha=.89), guilt about continued substance abuse (introjected motivation; alpha=.84), or a personal choice and commitment to the goals of the program (identified motivation; alpha=.85). External treatment motivation was positively correlated with legal referral, social network pressures to enter treatment, and was inversely related to problem severity. In contrast, identified treatment motivation was positively correlated with self-referral and problem severity, and was inversely related to perceived coercion (ps<.05). Hierarchical multiple regression analyses showed that referral source (i.e., mandated treatment status), legal history, and social network pressures did not predict any of 6 measures of client engagement at the time treatment was sought. However, treatment motivation variables accounted for unique variance in these outcomes when added to each model (DeltaR(2)s=.06-.23, ps<.05). Specifically, identified treatment motivation predicted perceived benefits of reducing substance use, attempts to reduce drinking and drug use, as well as self (and therapist) ratings of interest in the upcoming treatment episode (betas=.18-.31, ps<.05). Results suggest that the presence of legal referral and/or social network pressures to quit, cut down, and/or enter treatment does not affect client engagement at treatment entry.