The Harmony series does not belong to any single platform, instead encompassing all high-speed trains in China with roots in foreign technology, specifically CRH1, CRH2, CRH3 and CRH5.

Bombardier Transportation, Kawasaki Heavy Industries, Alstom and later Siemens joined the high-speed train manufacturing project that later became known as Harmony.

The signalling, track and support structures, control software, and station design are developed domestically with foreign elements as well.

The signalling, track and support structures, control software, and station design are developed domestically with foreign elements as well, so the system as a whole is predominantly Chinese.

However, in practical terms, issues such as maintenance costs, comfort, and safety make the maximum speed of more than 380 km/h (236 mph) impractical and remain limiting factors.