- East Rail was the first heavy rail in Hong Kong.
- Provides trunk services in high demand corridors. May feed heavy rail or ferry.
- Heavy rail has the lowest operating costs and provides a high level of service.
- Provides services in low demand corridors. May feed heavy rail, light rail or ferry.
- Provides trunk services in medium demand corridors. May feed heavy rail, light rail or ferry.
- The LRT has a much lower capacity than heavy rail, but is also much less expensive to construct.