Novice counselors may struggle to understand and follow ethical guidelines for boundary behaviors with clients. When counselors violate therapeutic boundaries, harmful consequences can result for clients and counselors. The purpose of this quantitative study was to examine the possible relationship between novice counselors' (NCs') attachment to supervisors and NCs' ethical perceptions and boundary practices. This study addressed the possible predictor variables of age, gender, relationship status, and practice setting. Bowlby's attachment theory provided the framework for the study. Survey data from 114 NCs were analyzed using descriptive statistics and hierarchical linear regression. Each regression analyzed predictors of age, gender, relationship status, and practice setting in model 1 and added level of attachment anxiety and level of attachment avoidance to supervisor in model 2. Findings indicated that NCs' level of anxious attachment predicted serious boundary violations (BVs). Those with higher levels of attachment anxiety reported more BVs and perceived more items as BVs. Level of attachment avoidance also distorted ethical perceptions; those high in attachment avoidance considered more items to be boundary crossings and BVs. The variables of age, male gender, and an urban practice setting significantly predicted higher reported boundary crossings. Males more often did not consider behaviors to be BVs, and more females agreed with expert perceptions of items which were neither a boundary crossing nor a BV. Age was significant but contrary to previous findings because in this sample, as age increased, reported BVs decreased. Findings may lead to changes in how counselor educators and supervisors train NCs to manage boundaries in therapeutic relationships.