Sit-ins or occupations of property or premises may constitute criminal offences such as trespass, obstruction and besetting, and give rise to civil actions such as trespass.
Sit-ins or occupations will often mean facing private security guards before police arrive.
Squatting is the act of making use of empty, disused and abandoned property. It allows people who cannot otherwise afford to rent or purchase a house or building to put an empty one to productive use.
Unlike in some other countries, there is no legal right to squat in empty, disused and abandoned property.
For information about the law and squatting in Melbourne go to the No Frills Melbourne Squatters Guide (much of the information will be useful for people in other parts of Australia as well).
Other resources include: The SUWA show on Community Radio 3CR
Social centres are an international activist initiative that aims to make use of self-managed space through autonomous decision-making. Social centres are the result of occupation movements that reappropriate property for activist and working class community space.
These kinds of squats are part of an international matrix of squatting movements with histories of supporting worker, peasant, student and community uprisings critical of private property systems and government power.
Again there is no legal right to occupy premises which are being used as a social centre.
For information about social centres see SCAN Social Centre Stories