| 1993 - present | President |
| M.J. Schiff & Associates, Inc. | |
| Upland, CA | |
| 1993 - present | Managing Director |
| Bell Geochemistry and Bell Geochemistry, Inc. | |
| 1990 - 1993 | Staff Member |
| Metals & Ceramics Division | |
| Oak Ridge National Laboratory | |
| Martin Marietta Energy Systems, Inc. | |
| 1989 | Post Doctoral Researcher |
| Oak Ridge Associated Universities | |
| Metals & Ceramics Division | |
| Oak Ridge National Laboratory | |
| 1988 | Part-time Consultant |
| Metals & Ceramics Division | |
| Oak Ridge National Laboratory | |
| 1986 - 1988 | Visiting Laboratory Graduate Researcher |
| Metals & Ceramics Division | |
| Oak Ridge National Laboratory | |
| 1983 - 1988 | Member of the Technical Staff |
| Space and Technology Group | |
| TRW Incorporated | |
| 1982 - 1986 | Post Graduate Research Engineer III |
| University of California, Los Angeles | |
| Los Angeles, CA | |
| 1977 - 1982 | Field Engineer |
| M.J. Schiff & Associates | |
| Upland, CA | |
| 1982 | Reactor Engineer |
| Connecticut Yankee Atomic Power Company | |
| 1982 - 1984 | Reactor Operator |
| University of California, Los Angeles | |
| Los Angeles, CA | |