The primary purpose of this research was to examine public high school counselors' career interventions practices and preferences in comprehensive school counseling programs. Secondarily, this study investigated how those career intervention practices support students' Individual Learning Plans (ILPs). The research questions guiding this study examined (a) career intervention practices and preferences, (b) the relationship between career intervention practices, preferences and selected explanatory variables, and (c) school counseling support for implementing the career component of students' Individual Learning Plans. The sample ( N = 84) was public high school counselors in a southern New England state. Utilizing an explanatory, sequential mixed methods design, Phase I, was a web-based survey with close-ended and open-ended questions. Cronbach's alpha (0.94) indicated internal reliability of the total scores. Descriptive statistics (frequency, percentages, means, standard deviations) characterized the respondents, public high school counselors ( N = 84). Multiple stepwise regression analyses examined relationships between the outcome variables and selected explanatory variables. Group interviewing expanded the survey data prior to comparative analysis of data from Phase I, Phase II, and the "Rhode Island School Counselor Survey Report" providing a deeper understanding of the findings. Respondents indicated 41 of 44 career interventions (93%) they practiced significantly comprised less of their comprehensive school counseling programs than preferred. A weak, negative relationship ( r = -0.30) existed between the Field-based taxon and five hours or less of annual professional development in the career domain where the adjusted R[superscript 2] = 7.4%. Top ranked emergent themes to examine Individual Learning Plans support were: delivery system; computer assisted career guidance systems; and multiple implementation barriers. Recommendations were to establish policies and protocols for implementing Individual Learning Plans and to support students' career development in schools. Several research topics are offered. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]