LTC Osborne enlisted in the Infantry in 1981 and attended One Station Unit Training at Fort Benning, Georgia.  He was commissioned into the Infantry as a Distinguished Military Graduate from Officer Candidate School in the fall of 1982.

       Following post commissioning schooling, he was assigned to 3rd Battalion, 187th Infantry, 101st Airborne Division where he served from 1983 to 1986 in successive assignments as Platoon Leader, Battalion Maintenance Officer, and Executive Officer of both rifle and anti-armor companies. While at Fort Campbell, he represented the Division in the 1986 Best Ranger Competition.

       From 1988 to 1991, LTC Osborne served in the 3rd U.S. Infantry (The Old Guard) where he was an Assistant S-3, Company Commander, and Deputy Regimental S-3.  After being selected as the McArthur Leadership Award winner for the Military District of Washington, he was reassigned as aide-de-camp to the Commanding General from 1991 to 1993.

        LTC Osborne served from 1994 to 1997 in Germany as a Staff Officer in V Corps G3 Operations (Frankfurt and Heidelberg); S-3 of 1st Battalion, 15th Infantry (Schweinfurt) and S-3 of Task Force 1-15, Operation ABLE SENTRY (Macedonia); and Task Force S-3 O/C at the Combat Maneuver Training Center (Hohenfels).

       From 1997 to 1999 LTC Osborne served as a North Atlantic Treaty Organization Staff Officer in the Supreme Headquarters Allied Powers Europe (SHAPE), Mons, Belgium, with special emphasis on integration of the New Member Nation's Reaction Forces.

       His awards and decorations include the Defense Meritorious Service Medal, the Meritorious Service Medal with two oak leaf clusters, the Army Commendation Medal with five oak leaf clusters, the Army Achievement Medal with 7 oak leaf clusters, Good Conduct Medal, the Armed Forces Service Medal, the UN Medal, the Ranger Tab, the Expert Infantryman's Badge, and the Airborne and Air Assault Badges.