The Future of Direct Mail
Warwick: In fundraising, I believe it's a mistake to use color and graphics so aggressively. Testing repeatedly shows that plain, businesslike appeals outpull flashy ones.
Friesen: Again, these are things to test. I've read/heard that personalization on outers ups response. I've read/heard that solid colored envelopes pull better than white. But who knows if it will work for every market, every brand, every mailing? You've got to do what you know/believe to be appropriate—then test, test, test.