In a meeting of negotiation, what will be your first important target to achieve ?

to arrive a Win-Win situation or Convince the other party.  

I would aim to arrive to a win -win situation

 Bargaining (give and take) process between two or more parties (each with its own aims, needs, and viewpoints) seeking to discover a common ground and reach an agreement to settle a matter of mutual concern or resolve a conflict. Noun form of the verb negotiate.

To discuss the terms and convince and clear out the point , whereby both party mutually agree the terms in order conclude the deal.

My first target to make the deal Happen!

It depends on demand of project and situation. At one certain time delivery of goods may be the prior constraint so we need to negotiate for best delivery thereafter for price and other commercial terms, while on the other part there may be adequate time and in such situations negotiation for price and other commercial terms pertaining to LD,Payment terms etc may be prioritized.

To convince supplier that  Buyer organization is open to any supplier

who gives best terms.

As far as the negotiation meeting is concerned, i would choose a "Win-Win" situation as major target.