Arturo Merzario established his team in 1977 after he was unable to secure a seat with an established Formula One outfit. He initially ran a customer March 761B car rather than building his own machinery, using this period to gather resources and data for what he envisioned as a fully self-constructed effort. During 1977 his best result was a fourteenth-place finish at the Belgian Grand Prix — the only occasion in the team's three-year World Championship career that one of their cars was classified at the finish of a race.
In 1978, Merzario entered a partnership with Swiss Formula One entrant Guglielmo Bellasi, providing the financial and organisational platform to build his own cars.
The team's first self-built car, the Merzario A1, appeared in 1978. Initially painted red, the car's livery changed to black before the Monaco Grand Prix. On eight occasions the A1 qualified for a race, but it retired seven times with mechanical failures. The lone exception was the Swedish Grand Prix, where the car finished but was classified as unclassified, eight laps adrift of the winner following a lengthy pit stop.
For the Austrian Grand Prix, a second A1 was entered — suspected by observers to be the old March 761B re-bodied. Alberto Colombo drove this car at the Italian Grand Prix, while Merzario took the newer chassis; Colombo failed to make the grid and Merzario's engine expired during the race.
The second A1 was revised into the A1B for 1979, with more elegant bodywork and revised front suspension under a new yellow and black colour scheme. The A1B qualified for two Grands Prix during the year but retired on both occasions.
The new A2 (designated A3 by some sources), designed by Merzario and Simon Hadfield, introduced a ground-effect wing-car configuration based on the original A1's underpinnings. Only one example was built. The car debuted at the United States Grand Prix West, though Merzario had to start that race in the A1B after the A2's front suspension failed. Its official debut came at the Spanish Grand Prix, where Merzario set the 26th qualifying time and failed to make the race. At the Belgian Grand Prix, Merzario crashed in qualifying and broke his arm; Gianfranco Brancatelli stood in for Monaco but also failed to pre-qualify.
Mid-season, Merzario and Bellasi purchased the assets of the collapsed Kauhsen team, including the WK chassis and Brancatelli's contract. The Kauhsen car was rebuilt by Giampaolo Dallara and renamed the Merzario A4, sharing the same Cosworth DFV engine and Hewland gearbox. Despite Dallara's expertise, the A4 proved slower than its predecessors and failed to qualify for every World Championship round. Its sole racing appearance came at the non-championship Dino Ferrari Grand Prix at Imola, where Merzario finished eleventh and last.
Financial difficulties prevented the planned development of an A5 variant from the A4 chassis. Merzario turned to Formula Two, entering a BMW-engined machine in 1980. He noted that the engine bay could theoretically accommodate a Cosworth DFV for a return to Formula One, but no such conversion was made. Results in F2 were limited, and the team switched back to customer March 812 chassis for 1981, recording two podium finishes with Piero Necchi. After a poor 1982 season Merzario built new cars for 1983, again without notable success. The team later contested Italian Formula 3 before Merzario stepped away from ownership in the mid-1980s.
Despite accumulating zero World Championship points, the Merzario team is remembered as an expression of the self-made constructor ethos that characterised the back of the Formula One grid in the late 1970s. The team built four distinct Formula One chassis — A1, A1B, A2, and A4 — across three seasons, each representing incremental attempts to close the technical gap to better-funded rivals. The team also absorbed the remnants of the Kauhsen programme, giving the latter's assets one final competitive outing before both projects were retired.