Modern versions of the launch system are still in use as of 2023[update], making it one of the most successful heavy boosters in the history of spaceflight.

The components of all Protons are manufactured in the Khrunichev State Research and Production Space Center factory in Moscow and Chemical Automatics Design Bureau[3] in Voronezh, then transported to the Baikonur Cosmodrome, where they are assembled at Site 91 to form the launch vehicle.

The moniker "Proton" originates from a series of similarly named scientific satellites, which were among the rocket's first payloads.

[10] As of June 2018[update], production on the Proton rocket is ceasing as the new Angara launch vehicle comes on line and becomes operational.

Mass-production of guidance, navigation and control system for Proton has begun in 1964 on "Communard" Industrial Association (Kharkov, Ukraine).

[16] In January 2017, the Proton was temporarily grounded due to the manufacturer, Voronezh Mechanical Plant, having substituted a heat-resistant alloy in the engines with a cheaper metal.

[17][18] In June 2018, the state corporation Roscosmos announced that the Proton rocket would cease production as the new Angara launch vehicle comes on line and becomes operational.

The initial Proton tests in 1965–66 only used the first two stages of the booster, the complete four-stage vehicle being flown for the first time in 1967.

The Proton M's improvements included lower stage modifications to reduce structural mass, increase thrust, and fully use propellants.

[24] On 2 July 2013, a Proton-M launching three GLONASS navigation satellites experienced a failure reminiscent of the 1960s disasters shortly after liftoff when the booster crashed near LC-39 at Baikonour, ending a 30-year unbroken stretch without a first stage failure; all future Proton flights were suspended pending investigation.

Due to the difficulty of installing the package incorrectly, it was widely suspected that it had been done deliberately by a disgruntled or drunk worker at the Khrunichev plant.

[citation needed] On 15 May 2014, a Proton-M/Briz-M carrying an Ekspress satellite suffered a third stage failure from a bad turbopump bearing.

On 21 October, another Ekspress satellite was left in a useless orbit when the Briz stage cut off 24 seconds too early.

On 16 May 2015, a MEXSAT communications satellite failed to orbit due to another third stage malfunction, the eighth Proton failure since 2010.

Khrunichev has initiated development of a set of phase IV enhancements in order to keep pace with market demands and the mass growth trends of commercial satellites.

The payload mass performance for phase IV has been increased to 6320 kg to a reference GTO orbit with 1500 m/s of residual delta V to GSO.

However, as KVRB is noticeably larger than Block D, the vehicle's aerodynamics, flight control, software, and possibly electronics would have to be reevaluated.

In addition, the launch pad can supply existing Protons with common hypergolic fuels from single sources.