I agree with the posts above that its important to have both business and interpersonal skills, but I believe its essential to have interpersonal skills to get deals done. Sales is all about not just getting a deal done, but relationships. As seen with this week's simulation, you want to not just make one deal, you want to have and maintain a good relationship with your customers so that continue to purchase your products. There's a great book called "Getting to Yes: Negotiating an Agreement without Giving In" by Roger Fisher and William Ury which I highly recommend if you're looking to obtain some negotiation strategies.

Interpersonal skills is very important in negotiation. I believe a good negotiator should have some qualifications- for example:
- Preparation and planning skill.
- knowledge of the subject matter being negotiated.
- Ability to think clearly and rapidly under pressure and uncertainty.
- Ability to express thoughts verbally.
- Listening skill.
- Judgment and general intelligence.
- Integrity.
- Ability to persuade others.
- Dealing with Difficult Situations.
- Seeking clarification on complex points.