Here's a link to an article in the NYT about some fantastic research on smoking cessation. These researchers tracked smokers for 32 years and made an interesting discovery. People who quit tended to do so groups. That is, when they and their friends tended to quit together. By extension, it's reasonable to assume that smokers' family and friends who also smoke make it harder for a smoker to quit. This is great research, for many reasons.
My background is in information processing psychology. I learned that problem solving was an individual affair. The research I studied included detailed models of memory for words, concept learning, problem solving, and decision making. The models were usually based on highly controlled laboratory experiments. A lot of the interventions for things like smoking are technologies directed at the individual: wearable patches, medication, spiked gum, etc.
But human behavior is social. It's all about families and friends. The smoking cessation research shows that very clearly. The interventions we need should account for both individual and group problem solving and behavior. Need more proof? How about the connection between family behavior and individual obesity? A lot of our successes and failures occur because of group dynamics - and that's where we need to look for solutions.
I know that a lot has changed since I was in school, and a lot has been done recently with modeling group behavior and problem solving. But we still look to technology for all of our fixes, when what we need to understand first is group behavior. Family and group interventions really call for a design approach to a workable solution - designers who can understand and design group problem solving behavior. If we get that right, the technology is the easy part.