Turn the applause light off?
Here is a post from Wellsung, upon which A.C. Douglas has already commented.
I tend to have a sliding scale. If the folks in the balcony want to applaud "Vissi d'arte" at every single Tosca from now until the Universe dies its heat death, that's fine by me. However, if they even think about applauding between movements of Mahler's 2nd, 6th, or 9th: they will probably be told (in no uncertain terms) to stop. Now. Heaven help them if they applaud any part of Parsifal. Yes, yes, I know: the Master is alleged to have applauded the Blumenmädchen scene, but he was the only person who could break etiquette at his music-dramas. Let us not even imagine what would happen if they made a noise after "Nur eine Waffe taugt."
I would say, simply, this when it comes to applause: don't do it until the end of an act or concert piece. It's rude, distracting, and a little gauche. Also, you'll look like a moron if you're the only person clapping. Not good to do with the symphony set. As to this bit,
Thus, I call on non-inter-movement clappers of the world to unite. Listening to nonstop applause after every movement is annoying. People interested in the music don't like it and performers don't like it. It's just an inefficient way to run a modern concert. And it's a piss-poor way to attract new classical music lovers. I mean, who are the wilting daisy rock enthusiasts who are so wounded when they find out the concert hall protocol is no clapping until the entire piece is over? Do these people actually exist? And do we even want them in the club? I mean, we still have some standards right?
Yes, Alex, we do have some standards these days. However, the A&R people are willing to sacrifice every single one of the those standards if they think that their doing so will pack one more rear-end into the cheap seats. When I saw Boulez do Mahler's 6th last month, there were empty seats - even on the first balcony (one of the better places to sit in Orchestra Hall, especially if you like brass). He hasn't done that piece there in a decade, and it's one of the Mahler symphonies that he "gets" and does well. Still, on a Friday night - people would rather shop at Water Tower Place than take a five-minute taxi ride down Michigan to hear one of the great symphonies under a great conductor do a powerful (brilliant, even) symphony. The pencil-pushers (and, remember, I am a math minor - more specifically, algebra) will do whatever it takes to sell seats. If that means turning these concerts into bloody populist rallies, then that's what they'll do.
In other words, if it gets them out of Louis Vuitton and into Orchestra Hall, they'll do it. Whatever the cost to the rest of us who care about music.
Mark my words and give it a couple years.