Some things I've heard from one senior business guy

• Technical knowledge - where You are aware of technology part of the story\project\product.
• Industry knowledge - where You can easily speak with business people, that You can understand what they are talking about, that You can also share some business knowledge and discuses with them at the almost the same level, maybe You can have also some insights from other participants in the same industry, that these people You are talking with are not aware. You can discuss with them about algorithms used in solution.
• Quality - You need to delivery quality products\services\solutions. Constant quality is also important. 
• Price - You need to have reasonable price. 

And he also said that people underestimate industry knowledge, and that this is probably one of the most important knowledge.

If You have all of these, Your customer will like You :-)