You can never go wrong with mustard yellow and grey. I love that it's both cheery & classic, and is a slightly more sophisticated, updated palette than the ever-popular pale yellow and grey.
In this outfit, the mustard blazer pairs well with the rich grey scarf, and I love just about everything in this room. The mix of mustard & grey furniture, the wood slab side table, and the travertine coffee table make for a stylish living room.