We have 24 parks under the Country Parks Ordinance. This law provides the authority to "encourage their use and development for purposes of recreation and tourism", "protect the vegetation and wildlife", and "preserve and maintain building sites of historic and cultural significance". The law explicitly states "[a] presumption against any new development".

Lower on the totem pole are so-called greenbelts. Sites are so designated to help conserve "existing natural environment … at the urban fringe, to safeguard it from encroachment by urban-type development, and to provide additional outlets for passive recreational activities".

Again, there is a presumption against development, but the constraints are not as strong as those for country parks.

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Hong Kong's land is 40 per cent parkland and about 14 per cent greenbelts. The less ecologically sensitive greenbelts may be developed before others.

In his public statements, Leung usually fudges parkland and greenbelts, so it's hard to know if he is talking about one or the other or both.

But before we do anything, let's start with "brownfield" sites, those zoned for industrial or commercial use but now mainly used for storage, car repairs or cargo-holding. They amount to an estimated 1,600 hectares. Let's develop the "brownfields" before we even talk about greenbelts and parks.

Meanwhile, more than 930 hectares are currently reserved for indigenous villagers to build single houses. Well, how about building public housing on them instead?