Using Multi-Option Trigger Fields
One of Campaigner’s most-used features is the ability to set a “trigger” for each mailing list. A trigger is simply a condition which states “member field X must contain value Y”. If this condition is met, the member is subscribed to the associated Campaign Monitor mailing list.
For example, you may decide that you’re only interested in members who select “Blue” in answer to the question “What is your favourite colour?”.

In this case Campaigner will check the
m_favorite_color custom member field (or whatever
you’ve called it) for the string “Blue”. All
pretty simple stuff.
But what if the question is “What are your preferred colour(s)?”, and the member has the option of choosing from a series of checkboxes?

This presents Campaigner with a real problem. If the member selects more than one colour the “trigger” condition will fail, even if one of the selected values is “Blue”.
The Campaigner Multi-Select extension solves this problem. Just download, install, and activate Campaigner Multi-Select, and Campaigner will automatically handle triggers on member fields containing multiple values, no additional configuration required. Single value trigger fields are unaffected.