Essence of model application for vocational identity is determined. Modeling is seen as a way to «objectify» and «verbalize» contradictions among various choice factors and career plan components arising at various stages of personal development. Diverse models of vocational counseling are considered. Ways to use models (in the form of identity analysis and self-evaluation schemes) to reveal most obvious contradictions in career development are shown. Demands placed on developers of online play techniques are considered on the example of a new online play test «Zerkalo uspeha» («Success Mirror»). Special attention is paid to the problem of soundness and reliability of expert systems used in designing online play techniques for today’s career guidance.