In the alternating loop model streetcars are given priority, with separated lanes in the centre of the street for both eastbound and westbound streetcars.
It is referred to as an alternating loop because every other block vehicle access is limited to local traffic, meaning delivery vehicles, taxis and people who work and live on the block. The alternating blocks will have full public access. No vehicles will be able to make a left hand turn, crossing the streetcar lanes.
In this model there is also extended "bump outs" on the sidewalk on the alternate side of the street being used for vehicle access, giving pedestrians more space.