The direct predecessor of the Baron was the Beechcraft 95 Travel Air, which incorporated the fuselage of the Bonanza and the tail control surfaces of the T-34 Mentor military trainer.

The first Baron included the fully-swept vertical stabilizer of the Debonair while still retaining the four to four+five place seating of the Travel Air.

The early Baron 55, A55 and B55 were fitted with 260 hp (190 kW) Continental IO-470 engines and had gross weights of 4880 to 5100 lb (2,200 to 2,300 kg).

Additionally, the aircraft tend to exceed the aft center of gravity (CG) limit with all six seats occupied and no baggage in the nose compartment to act as counterbalance.

When introduced in 1967, it was the fastest Beech aircraft, rivaling even the early King Airs sold at the time.

The entire fuselage was repositioned forward on the wing to address the aft CG issue that plagued the short-body models.

[20] The larger fuselage and improved rear-cabin access have made the 58 far more popular with commercial air charter and cargo operators than the smaller 55 and 56.

These variants were powered by turbocharged Continental TIO-520s of 310–325 hp (230–240 kW), had an increased 6100–6200 lb (about 2800 kg) gross weight, and were certified under FAR23 with a new type certificate.

The redesign provides a more industry-standard control arrangement and increases instrument panel space, but the aircraft lost the option of having a single yoke, which enhanced comfort for a passenger or relief pilot in the right-hand seat.

The current production version is the G58, featuring a glass cockpit, improved passenger cabin and changes to selected airframe details.

[21] The T-42A Cochise is a military version of the Baron 95-B55 for use by the United States Army as an instrument training aircraft.