Boycotts are a very ancient and common method of social, political or economic non-cooperation. There are many different types of boycotts including social boycotts, rent withholding, international consumer's boycotts, producer's boycotts, worker's boycotts and trader's boycotts.
A consumer boycott involves the mass refusal to purchase or use a particular product or service for a variety of reasons. Defamation may be an issue to consider when considering a boycott.
Also see Legal threats to silencing activists
Trade Practices Act
The secondary boycott provisions of the Trade Practices Act 1974 (Cth) (s.45D) make participation in a 'secondary boycott' unlawful. A secondary boycott occurs when two or more people act together to hinder or prevent the supply of goods and services from one party to another party.
Secondary boycotts often occur in an industrial relations context. However, environmental activists should also be aware of s.45D, because the definition of secondary boycott is very broad, and can include routine actions taken by individuals and groups to protect the environment.
If the main purpose of your action is related to environmental protection or consumer protection, you will not be liable under s.45D. This is so whether your group is an incorporated association or not. Unfortunately, however, this exemption provides no protection to actions aimed at protecting other important social values, such as human rights or Aboriginal heritage.
From: Fact sheet: Defending Yourself C) 2004 Environmental Defender's Office (Ltd) NSW
For information on strikes also see Trade Unionists section.