While interviewing a client today, she mentioned that her ability to influence was attributable, in part, to her use of the "love sandwich." In fact, her previous manager had asked her whether she had learned this technique in management training (she had not), as she did it with particular finesse.
Funny thing is, I had heard someone discuss research on this topic quite recently, on a CBC interview.
Well, you may be wondering what is this delicacy? Not a meal at all, it uses the noun "sandwich" more like a verb, in that one sandwiches a negative message between two positives.
The CBC interviewee, whose name escapes me, cited recent studies that show that an open-faced sandwich works best. Begin a tough message by sharing good news, positive reinforcement, recognition of accomplishments or work well done. Only then add in the improvement you'd like to see or refer to the change you see as necessary. You will find that the message, constructive criticism, observation is received quite well.
Useful at work, it is likely also useful at home. Give it a try and tell me if the research is substantiated!