I've always found conferences to be inspiring and rejuvenating. But, I think you need to know your goals before deciding to attend a convention.
People ask me which conference they should attend. The answer is: It depends.
Let's look first at the differences I see between a workshop, a conference, and a convention.
To me, a workshop is a hands-on, intense learning experience. I would go there with paper and pen and expect to be taught something and receive lots of handouts. The workshop might be taught by one person (if only a couple of hours long) or several people (if days long). My goal in attending would be to learn something, with a secondary purpose of networking. Therefore, when choosing a workshop, I would look at what the topic is and who is leading the class.
I see a conference as being longer than a workshop, first of all. Secondly, while it may have an overall theme, such as "craft of writing" or "agents" or "writing the romance" or "nonfiction," I expect it to have multiple tracks of lectures or mini-workshops on subjects related to the overall theme. And thirdly, it will have more people in attendance. Once again, I sign up for the conference because it deals with a subject I'm interested in, but, just as important, are the speakers and attendees. In choosing, I would consider what stage in my career I'm at: Do I want help in the basics of writing? Am I at the point where I need an agent? Do I want to learn about a particular genre? Am I searching for directors, producers, or other screenwriters? But the theme of the conference isn't always the deciding factor. I may feel I've moved beyond the basics of writing, but a certain conference with that as its theme has several speakers or attendees with whom I really want to network.
And, finally, conventions, to me, are huge deals. Lots of people, lots of talks and panels. These are networking heaven. Yes, you can go to hear writers or agents talk on subjects you're dying to learn about, but your primary goal in attending a convention is to meet people, exchange business cards, make contacts and friends, tell people about your book or manuscript, and have fun. (I'm talking the kind of fun where you meet favorite authors or laugh at dinner with other writers and their agents -- not the kind of fun where next year you see Writers Gone Wild videos of yourself dancing naked on the beach.)
So, what conference, workshop or convention you should attend depends on what you are looking for and want to get out of the experience.
3 weeks ago