  A negotiating team is a group of two or more agents who join together as a
single negotiating party because they share a common goal related to the
negotiation. Since a negotiating team is composed of several stakeholders,
represented as a single negotiating party, there is need for a voting rule for
the team to reach decisions. In this paper, we investigate the problem of
strategic voting in the context of negotiating teams. Specifically, we present
a polynomial-time algorithm that finds a manipulation for a single voter when
using a positional scoring rule. We show that the problem is still tractable
when there is a coalition of manipulators that uses a x-approval rule. The
coalitional manipulation problem becomes computationally hard when using Borda,
but we provide a polynomial-time algorithm with the following guarantee: given
a manipulable instance with k manipulators, the algorithm finds a successful
manipulation with at most one additional manipulator. Our results hold for both
constructive and destructive manipulations.
