The Melbourne Metro 2 (MM2) is a tunneling rail plan proposed by the Public Transit Victoria (PTV). This metro style train would run through a tunnel that connects Newport and Clifton Hill. It is part of a larger project called the Network Development Plan (NDP), which is a long term solution in public transit to try and counteract the exponential increases in population. If this metro is constructed, passengers will be able to be service over 20,000 people every 2-5 minutes thereby increasing the overall capacity for the Werribee and Mernda lines. The project is estimated to cost $14-20 billion AUD.

Melbourne has an incredibly high growth rate, and is expected to see some major increases in its population within the next few years. A rise in population statistically means a proportional increase in demand for public transit. The MM2 will give citizens more options for commuting in, around, and outside the city. Currently at a population of 5 million, Melbourne is looking to have a population increase of 1 million people in the next 15 years.