Systems engineering has become a commonly practiced discipline in many ground-based telescope projects over the last decade. Invented by the large defense and aerospace companies decades ago, space astronomy projects have long embraced systems engineering. While it is much easier to fix problems after the fact, ground-based projects have taken longer to embrace this approach. As ground-based projects have grown in size and complexity, discovering the benefits of a systems approach has taken time. The up-front costs should be compared to the intended savings at the end of a project in order to find a balance in applying systems engineering tools. Based upon size and complexity of a project, one might expect a different balance in the rigorous application of systems engineering discipline when applied to the ground-based systems of today, The question is, as future ground-based systems increase an order of magnitude in complexity and cost, will this push the systems implementation closer to that of complex space systems? Thoughts will be presented for future giant telescopes based upon experience outside of astronomy, as well as systems implementation on the Gemini 8-meter Telescopes Project and for the new Advanced Technology Solar Telescope (ATST).