Best way to get more involvement in librarians' association groups

[Deanna King]

Our group, ECLA of Southern California, has a core of 20 or so great people who attend most of our meetings (2 times a year) and pay dues ($5) regularly. 

We also have quite a few librarians who just don't make most meetings and don't pay dues (even though they are so reasonable).  They are busy running active libraries, and we'd love to have their participation!

Do any of you have suggestions for how to encourage more involvement from these folks?

And what kinds of topics or meeting formats do you find draw in the most people?

We did just do a book repair workshop in August, and that drew in a larger crowd.  Our region is 4 counties and probably 100 miles in diameter, roughly.

Thanks for your suggestions!

Deanna