Effective design collaboration at Heap involves using structured documents like the Problem Brief and Design Brief to ensure alignment and clarity before significant design work begins. The Problem Brief outlines the issue to be prioritized, while the Design Brief collaboratively describes potential solutions without delving into detailed mockups, allowing for early-stage feedback and adjustments. This approach helps avoid wasted efforts by enabling discussions on feasibility and priorities with engineers and product managers early on. The design brief also plays a critical role in product quality reviews, which focus on balancing product quality, project scope, and timelines without getting bogged down in design specifics. Although the high-level nature of the design brief carries some risk of changes during implementation, the benefits of early decision-making and collaboration are deemed worthwhile. The process also includes discussions on trade-offs, user journeys, and considerations of edge cases, ensuring a comprehensive yet flexible framework for ongoing design evolution.