Birds also enter the food chain through less formal channels, including direct supply to consumers and via local retailers and restaurants.

We discovered a flexibility in agencies that we wouldn't have if formal channels were all we had to work with.

Bring the issue up first in an informal setting, and if that doesn't work, then go through formal channels.

This allowed him to access information that might otherwise have been denied through formal channels.

This can be done through formal channels, such as workshops, training and conferences; or through online networks deploying social software and social networking services.