DB Plans

My brother is 61 years old and looking for tax-shelter opportunities. His wife makes a lot more money than he does and they don't need his income to live on. She is a W-2 employee and he is a contractor. Can someone direct me to a source that would outline how a defined benefit plan would work in his case? He said he plans to work another 10 years. His income is comfortably over $56K a year and comfortably under $272K, which I think are relevant numbers for this kind of plan.