The most successful advocacy campaigns appeal to a broad base of organizations and individuals. Broad appeal will gather more support for your campaign AND give lawmakers that rare (and desirable) chance to make many groups happy by passing one piece of legislation. Building a coalition makes it possible for a group of "like-minded" organizations to select policy priorities and campaign together for one policy at a time, ensuring a higher likelihood of campaign success.
Effective coalitions focus on specific campaigns, rather than a general cause. Advocacy campaigns keep coalition members engaged because they work toward policy goals that are important to each individual member but can only be achieved as a group. Your coalition will be most effective if it brings together four layers of members.
Coalition building is a relatively easy step; coalition maintenance is often more challenging but equally valuable. It is important for all members, regardless of organization size or resources, to feel like they played a part in the success of a campaign. Otherwise you may find that you do not have a coalition for your next advocacy campaign!