The Health Belief Model (HBM) is a popular behaviour change model among psychology and social scientists. However, it is not generally applied in its entirety as only selected constructs are used in research. In an attempt to test its applicability for use in the 21st Century, the complete model is evaluated for its predictive quality relating to safer sex behaviour. Each of the model’s original six variables were tested to predict condom use among 100 Canadian prisoners, behaviour prior to incarceration. Analyses included tests of chi-square and logistic regression. Findings indicate it is necessary to create a new factor of sexual “partner type” in order for the HBM to predict condom use. Condoms are generally used with casual and anonymous partners, but not with steady partners. These “steady” female partners are at risk for contracting HIV, STDs or Hepatitis from their partner if condoms are not used, particularly when a prisoner assumes the woman is “clean” and “won’t give AIDS” to him. Such attitudes put sexual partners at risk for potential exposure to prisoners’ own earlier risk behaviours. Educational development for marginalized women associated with the inmate population is explored.