Final answer:
Trust building is the necessary relationship skill during the interfacing activity of building a strategic alliance.
Step-by-step explanation:
The relationship skill that is necessary during the interfacing activity of building a strategic alliance is Trust building. Trust is essential for a successful strategic alliance as it creates a foundation of mutual understanding, transparency, and reliability between the partnering organizations.
For example, when two companies are collaborating on a project, trust enables them to share sensitive information, make joint decisions, and have confidence in each other's abilities and commitments.
By building trust, organizations can strengthen relationships, navigate challenging situations, and work towards common goals effectively.