I broke down what the research says about how to get the most out of intensive speech therapy in [this post](https://www.reddit.com/r/Stutter/comments/pykg7q/quick_hits_what_the_research_says_about_improving/). TL;DR: Intensive speech therapy does bring dysfluency to a minimum, but you also need a maintenance program that involves real-world application or you're likely to regress right back to where you started. - Or, you can do "metronome training" on your own, which also increases fluency but is much less of a time/money investment.