XM1220 Caiman 4x4 / Caiman Light
XM1230 Caiman Plus 4x4 / Mama Bear
Caiman 6x6

The Caiman series of MRAPs was based on the Family of Medium Tactical Vehicles (FMTV) built by BAE Systems, as well as the Low Signature Armored Cab (LSAC), a crew protection kit for the FMTV series, also developed by BAE Systems. The Caiman family of vehicles combined many features and automotive components from these systems. The Caiman vehicle was originally designed only as a 6x6 type, fitting the MRAP Category II requirements. Later a 4x4 Caiman Light variant was developed. Under the MRAP II program, protection against Explosively Formed Penetrators (EFP) was developed, and an improved version of the Caiman Light, the Caiman Plus was unveiled. This vehicle, also referred to as the "Mama Bear," could be identified by the large applique armor boxes fitted to the vehicle sides.

Initially, the vehicle was offered by Stewart & Stevenson Tactical Vehicle, a division of Armor Holdings, Inc. In July 2007, BAE Systems acquired Armor Holdings in its entirety and renamed it Global Tactical Systems, which became responsible for the Caiman product line. BAE Systems also acquired the FMTV truck line, on which the Caiman was based, another product of Stewart & Stevenson Tactical Vehicle. Armor Holdings had been awarded its first contract, valued at $518 million, earlier in July 2007. Global Tactical Systems completed the contract.

In December 2007, BAE Systems announced it had received 2 follow-on delivery orders worth a total of $1.1 billion under an existing US Marine Corps' Mine Resistant Ambush Protected (MRAP) contract for, among other items, 668 Caiman Category I vehicles.

In January 2008, BAE Systems anounced that it had been competitively selected to develop and produce prototypes of the next generation of Mine Resistant Ambush Protected (MRAP) vehicles, MRAP II, with the award of a $5.7 million contract from the MRAP Joint Program Office. Under the MRAP II program, the government could order the production of up to 20,500 MRAP II vehicles, testing, spare parts and logistics support. As with the original MRAP vehicles, the MRAP II vehicles would be split into 4x4 and 6x6 vehicles, designated Category I and Category II rsepectively. BAE's Category I vehicle would be based on the 6x6 Caiman MRAP.

In March 2008, BAE Systems announced that it had received 2 follow-on delivery orders for Mine Resistant Ambush Protected (MRAP) vehicles totalling $715 million from the US Marine Corps. Among other items, under the contracts, the company would build and deliver 1,024 Caiman-based Category I vehicles.

In October 2008, BAE Systems unveiled the Caiman Light, a 4x4 variant of the 6x6 Caiman MRAP. The vehicle offered comparable protection to the larger 6x6 vehicle, but at 18 tons, was two-thirds the weight of its predecessor. The 4x4 vehicle maintained an 85 percent commonality in parts with the 6x6 vehicle, had the same electronic controls, and could be fitted with all-wheel steering, providing a turning radius of less than 20 feet. BAE would produce the armored hulls for the vehicle at its Fairfield, Ohio facility before shipping them for final assembly at its Sealy, Texas facility, where other members of the FMTV series were also assembled.

In November 2008, BAE Systems stated that it had completed some 2,868 Caiman vehicles for the US military since January 2007. Production of both the Caiman and RG-33 vehicles ended on 20 November 2008. BAE Systems said at the time that it was in discussions with the US Army about transitioning to a fleet strategy, based on the fact that the Caiman vehicle family shared so much commonality with the FMTV family already in widespread service.

In February 2009, BAE Systems announced it had delivered 2 different M-ATV (Mine Resistant Ambush Protected All-Terrain Vehicles) prototypes to the US Government for 2 months of testing and evaluation. The version would be produced by the company's Global Tactical Systems subsidiary would be based on the 4x4 Caiman Light MRAP.

In May 2009, BAE Systems announced that it had been awarded contracts to provide the military with 2 versions of a new armored all-terrain vehicle, as part of the M-ATV program. This included the derivative of the 4x4 Caiman Light MRAP developed by Global Tactical Systems.

In June 2009, BAE Systems announced that it had been awarded a contract modification worth $19 million from the US Marine Corps Systems Command to upgrade 1,800 Caiman Mine Resistant Ambush Protected (MRAP) vehicles. The upgrades were to increase the functionality and dependability of several of the Caiman's systems and individual items. Work would take place at the Kuwait Refurbishment Facility and was anticipated to be completed by July 2010.

In early 2010, BAE Systems introduced the Caiman Multi-Terrain Vehicle (MTV) in response to user needs. The Caiman MTV was said to provide an effective combination of interior capacity, tactical mobility, operator comfort and survivability. The basic 6x6 MTV troop carrier configuration had, among other features, an independent suspension system developed by Arvin Meritor and a powertrain upgrade developed in response to an MRAP performance specification. In September 2010, BAE Systems' announced that its subsidiary Global Tactical Systems had been awarded a contract to upgrade 1,700 existing Caiman MRAPs to the MTV standard. The Caiman MRAP family had been the only family not fitted with the Oshkosh Defense TAK-4 independent suspension system, which had been purchased as an upgrade option for existing MRAP types.