Brian Urlaub, speaking as part of MIT's RES.ENV-007 Geothermal Energy Networks course during IAP 2025, introduces the core concepts and considerations involved in designing ground source heat pump networks, known as GENs. The session covers the practical factors engineers weigh when planning a networked geothermal system, including how boreholes, piping, and shared infrastructure interact across a neighborhood or campus scale. Urlaub, affiliated with HEET, draws on real design tradeoffs rather than abstract theory, framing GENs as a thermal energy alternative to conventional heating and cooling systems. The talk fits within a broader IAP course aimed at engineers and planners working on decarbonizing building heat, and this installment focuses specifically on the technical starting points for sizing and laying out a geothermal network before deeper design sessions follow.