A quasi-experimental study was conducted within the context of the University of North Florida's EXCEL (Excelling in Clinical Education Learning) teacher preparation program to investigate the impact of three types of educational treatment on the attitudes toward diversity of preservice teachers. Data were collected and analyzed based on the pretest/posttest measures of three self-reporting instruments: Cross Cultural-Adaptability Inventory, the Cultural Diversity Awareness Inventory, and the Bogardus Social Distance Scale. The preservice teachers (N = 208; K-12 regular and special education majors) experienced the following treatments: (1) informal seminar studies of multicultural education issues accompanied by a field experience in a non-culturally diverse public school classroom; (2) informal seminar studies of multicultural education issues accompanied by a field experience in a culturally diverse public school classroom; and (3) no seminar studies of multicultural education issues and no field experience in a public school classroom. The weekly on-campus seminars were conducted by four clinical educators (master teachers from neighboring districts on alternative assignments for two years). In addition, with-in group attitudinal differences toward diversity of preservice teachers enrolled in the fieldbased seminars were examined based on variates of field placement, seminar instructor, gender, age, race, educational major, association with culturally different people, and teaching grade level. Examination of relationships between groups, based on ANOVA and ANCOVA results at the .05 level of confidence, reveals the followings: (1) no significant differences were found in attitudes toward diversity of preservice teachers enrolled in the field-based seminars focusing on issues of diversity, but significant differences were found between the control and experimental groups at both the onset and end of the study (experimental group had higher mean scores), (2) significant differences were found within-groups for the demographic variates of seminar instructor, age, race, association with people of diversity, and grade level, (3) significant (although minimal) differences were found in attitudes toward diversity between preservice teachers enrolled in the seminars focusing on issues of cultural diversity as compared to the control group of students not enrolled in the seminars (experimental groups had higher mean scores), (4) no significant differences were found between the experimental groups to support the assumption that field experiences within Culturally diverse settings have a positive effect on the attitudes of preservice teachers toward diversity, and (5) although positive significant differences were found between the control and experimental groups following the completion of the multicultural seminars, all three groups remained at the social distance preference level "having merely as a speaking acquaintance" in working with the culturally different as measured on the Bogardus and far below the normed population on the Cross Cultural Adaptability Inventory factor Flexibility/Openness (FO).