Senior-Level (SL) & Scientific and Professional (ST) Positions

Senior-Level (SL) Positions

Pursuant to 5 U.S.C. 5108, OPM determines the maximum number of positions that may be classified above GS-15. Within an agency subject to the Senior Executive Service (SES), a position classified above GS-15 that meets one or more of the SES functional criteria in 5 U.S.C. 3132(a)(2) must be established in the SES. Thus, an SL allocation issued by OPM may only be used for a position the agency has determined is properly classified above GS-15 based upon non-executive duties and responsibilities, which may include research and development functions consistent with published position classification standards and guides and accepted classification principles. SL may be used for an executive position in an agency not subject to the Senior Executive Service.

Scientific and Professional (ST) Positions

Pursuant to 5 U.S.C. 3104, OPM determines the maximum number of scientific and professional (ST) positions that may be established in an agency.  An ST position must be engaged in research and development in the physical, biological, medical, or engineering sciences, or a closely related field. Within an agency subject to the Senior Executive Service, a position classified above GS-15 that meets one or more of the SES functional criteria in 5 U.S.C. 3132(a)(2) must be placed in the SES; and 5 U.S.C. 3104 specifies the ST authority shall not apply to an SES position.  Under 5 CFR 319.203(b) an ST allocation issued by OPM may only be used for a position the agency has determined is properly classified above GS-15 consistent with published position classification standards and guides and accepted classification principles.  ST may be used for an executive position responsible for research and development functions in an agency not subject to the Senior Executive Service.