Continuation of this requirement is essential and supports the use of a sole-source approach because the requirement necessitates professional support services provided by personnel with the knowledge... Continuation of this requirement is essential and supports the use of a sole-source approach because the requirement necessitates professional support services provided by personnel with the knowledge and capability to identify, analyze, and execute accepted principles, methods, and guidelines associated with routine and specialized administrative tasks and functions for the Office to Monitor and Combat Trafficking in Persons (TIP).