Abstract: Aspects for a heterogeneous computer network system with unobtrusive cross-platform user access are described. In an exemplary system aspect, the system includes a plurality of computer systems coupled in a network, each of the plurality of computer systems operating according to one of a plurality of operating system platforms, each operating system platform having an associated security mechanism. The system further includes an enterprise directory included on at least one server system of the plurality of computer systems, the enterprise directory configured for security interception to allow an authorized user access among the services of the plurality of computer systems without affecting the associated security mechanisms of the plurality of operating system platforms.