The present four field studies explored the effectiveness of multiple prevention techniques designed to increase the frequency of cashiers' identification (ID)-checking behaviors from a customer-focused and cashier-focused approach. Studies 1 and 2 examined customer-focused approaches, whereas Study 3 examined a cashier-focused approach. Study 4 examined a combination of the cashier-focused and customer-focused approaches. From a customer approach, Study 1 investigated the use of four prompts (a no-prompt control, an antecedent only, an antecedent with a positive consequence, and an antecedent with a negative consequence) at encouraging cashiers to ask customers for their ID during a credit purchase. Research assistants (RAs) visited various stores and made credit purchases, while displaying one of the four prompts covering their card's signature line to the cashier during check-out. The results showed RAs were checked for ID the most when using the prompts containing the antecedent and consequence, which was checked for ID significantly more than the no-prompt control. Study 2 (also a customer approach) attempted to replicate Study 1 in a non-college community. Using a similar methodology as Study 1, the results showed RAs were checked for ID the most when using the prompt with the antecedent and positive consequence, which was checked for ID significantly more than the no-prompt control. From a cashier approach, Study 3 investigated the use of a goal-setting and prompt intervention led by the restaurant manager to increase the frequency of cashiers' ID-checking behavior. Using an A-B-A (Baseline-Intervention-Withdrawal) reversal design at one of two restaurants, the results showed the intervention restaurant's percentage of ID-checked purchases increased from Baseline to the Intervention phase. But, it decreased slightly during the Withdrawal phase, showing functional control but also some maintenance over the target behavior. The percentage of ID-checked purchases at the control restaurant was almost nonexistent throughout the study. Study 4 investigated the impact of using two intervention approaches (i.e., the customer and cashier approach) as opposed to one (i.e., the customer approach) to increase the frequency of cashiers' ID-checking behavior. While the A-B-A phases were occurring in the restaurants used in Study 3, RAs entered the restaurants and displayed an antecedent and positive consequence prompt to the cashiers during a credit purchase. The results of Study 4 partially supported the hypothesis. The cashiers in the intervention restaurant significantly checked more RAs for ID when two intervention approaches were combined than when only one intervention approach was used during Baseline, but not during the Withdrawal phase. / Ph. D.