Research on attitudes and training outcomes suggests that employees with positive attitudes have better job performance and involvement in the workplace. As the training environment has changed from teacher-centered to learner-centered, both trainers and trainees are responsible for training efficiency. The purpose of this study was to analyze the factors that contribute to being an effective trainer. This research also provided suggestions to help employers and managers effectively select trainers who could increase training efficiency and productivity and reduce production costs;An attribute rating scale of 66 items was developed to effectively select potential trainers from current employees. A research survey was then conducted with the manufacturing industry in the state of Iowa. T-tests were used to show the differences between trainers and manufacturing employees, and differences between male and female employees. A factor analysis was conducted with 205 usable responses to identify those factors that contribute significant differences among employee attributes. Following the factor analysis, an ANOVA was adapted to determine the relationships between the independent variables (i.e., status, gender, education level, field, work experience, and experience in training) and dependent variables (i.e., interpersonal skills, behaviors, knowledge and skills, and personalities). Fourteen factors were described which have significant correlations to independent variables;The findings indicated that there are significant differences between trainers and manufacturing employees based on communication skills, relationship orientation, task orientation, insistence, concept toward training, logical thinking, and self-identity. Also, attribute differences among trainers and manufacturing employees could be attributed to variations among status, gender, education level, professional field, work experience and the number of training activities attended. It is recommended that follow-up research be conducted to evaluate the training performance of employees who participated in this research study, particularly those who were selected to become in-house trainers based on their attributes.