According to defence publication Jane's Information Group, by 1985, the A129 was considered to be a comparable attack helicopter to the American-built McDonnell Douglas AH-64 Apache, and showed potential on the export market.

[9][10] However, the LAH project collapsed in 1990 following Britain and the Netherlands independently deciding to withdraw from the program and eventually procure the AH-64 Apache instead.

The A129I featured a five-bladed main rotor (early production aircraft had employed a four-bladed main rotor), a pair of LHTEC T800 engines (replacing the Rolls-Royce Gem engines of Italian Army Mangustas) and an upgraded transmission; the A129I were also provisioned with new weapons and electronic warfare systems.

Following a highly protracted selection process, in September 2007, an order was issued for 51 TAI/AgustaWestland T129 ATAK helicopters, a variant of the A129 International.

As such it has several original aspects to its design, such as being the first helicopter to make use of a fully computerised integrated management system to reduce crew workload.

[16] It was decided that much of the helicopter's functionality was to be automated; as such, parts of the flight and armament systems are monitored and directly controlled by onboard computers.

[16][5] The A129 is able to be operated in various capacities, including to perform anti-armour, armed reconnaissance, ground attack, escort, fire support and anti-aircraft missions.

[5] One key feature present on the engines is the incorporation of infrared suppressors, which act to reduce the aircraft's heat signature and thereby improve survivability.

[16] One of the key protective measures incorporated onto the A129 include the electronic warfare and SIAP (Single Integrated Air Picture) self-protection suite.

[17] Elements of the mission interface systems and the onboard software integrated onto later aircraft were produced by Selex Galileo.

[17] On the AW129D, Rafael Advanced Defense Systems's Toplite III sight is used as the primary targeting system; it is able to act as a FLIR and has both manual and automatic target tracking modes, Toplite also provides a greater detection and identification range than the 1970s era HeliTOW sensor it replaced.

[25] In 2011, AgustaWestland was part-way through modifying a total of 24 A129s to the new ARH-129D aerial reconnaissance standard, as well as the manufacturing of a further 24 new-built ARH-129Ds for the Italian Army.

The A-129 proved to be suitable in the peacekeeping role and well-suited to operations in hot climates; the type was reported to have been highly reliable and extremely flexible during the deployment to Somalia.

These upgrades, which are to enter service prior to 2020, largely focused on increasing the A129's endurance, speed, situational awareness, and information-handling capabilities; other goals included a reduction in pilot workload and integrating the aircraft with future tactical UAVs.

[28][29] In March 2016, the Italian government announced that it was deploying four A129 attack helicopters and four NHIndustries NH90 transport helicopters along with 130 personnel to the Kurdistan region of Iraq to perform combat search and rescue mission as part of a multinational effort to help combat Islamic State militants within the region and specifically to protect the Mosul Dam.