For instance, one day she would do her sit/stays perfectly; the next, she would act as if she'd never received a day's training in her life (as if she were raised by.. you know -- wolves). Those were the days when it behooved me to be even more consistent, to reinforce even more positively and to get creative. I would make a game of it by getting her into a sit/stay, hiding somewhere, and then releasing her to come find me: doggie hide-and-seek.
So, from the very humble beginning of a basic “sit;” over time and in small, realistic iterations, happily benefiting from the little bit of value delivered along the way, I now have a dog who does not jump on strangers and who has about a 98% success rate with not jumping on her favorite people. As for jumping on other dogs, well.. I think I'll let that one slide: the other dogs don't seem to mind, after all.