I posted about this some time ago, thought it was worth a repeat, seeing how I didn't get any 'concrete' comments about how and when to prune a Clematis.
We all love a great flowering Clematis Vine, don't we? It doesn't matter what flowering category your Clematis falls in--flowering will eventually slow way down without pruning...wouldn't that be sad? Unpruned, new growth will only be at the ends of the vines--this is where the flowers will bloom. Photos taken yesterday.

Pruning Clematis seems to put fear in even the most experienced Gardeners.
Heres a little of what I remember reading.
1. Spring Bloomers--Prune back when they finish blooming, (do avoid cutting into very old wood)
2. Summer and Fall Bloomers--Prune when dormant or when just waking. If you want it to remain long, prune to healthy leaf bud.
3. Repeat Bloomers--TRICKY, if Spring is the big show prune after flowering--if late season is the show prune while dormant. Do not prune like 1 and 2 --treat more like a trim.

I purchased a few Clematis on sale last Spring, they did not flower but are putting on new growth. I think the tags are incorrect on them, so I have to take the wait and watch approach. The Clematis featured here bloomed like wildfire early Spring and now it's blooming again. I pruned it lightly after the Spring show. This must be a Repeat Bloomer...
How and when do you prune your Clematis? Do you know the names of them, if so, please include them in your comments. Perhaps you have better advice for pruning than I do. Please feel free to share........this is one gardener that can use all the advice she can get!