The objective of this research is to understand the historical evolution of software development, identify desirable characteristics of methods supporting agile for hardware, and recommend potential methods enabling agile development of hardware products. As technology and markets change, product development increasingly operates in a volatile, uncertain, complex, and ambiguous (VUCA) environment. While originally applied to software development, organizations are starting to see opportunity in adapting the agile philosophy for hardware development. A comparison of philosophies is made between waterfall, spiral, and agile development. The historical evolutions of software development, after agile, including Continuous Integration Continuous Deployment (CICD), Development and Operations (DevOps), and Development Security and Operations (DevSecOps) is presented. Benefits and challenges in the application of agile methods for hardware are presented. Benefits include improvements in flexibility in response to change and soft factors such as team communication, transparency and commitment. However, many challenges still remain. These are grouped into theme areas including lack of product flexibility, difficulty in separating deliverables, challenges with breaking down tasks within a sprint, changes needed in culture and mindset, difficulty scaling beyond pilot programs, team distribution, and development of an integrated approach across the product lifecycle. Potential methods to aid in the adoption of agile for hardware are discussed using the phases of the hardware development lifecycle as a framework. Recommended methods include the adaptation of Model Based Systems Engineering (MBSE) for problem definition, the use of generative methods for design, the application of Virtual Reality (VR) for prototyping, leveraging additive manufacturing for production, and favoring software defined systems to help in operations. By reducing both the duration and person-hours, these methods enable higher iteration rates for hardware products needed for an agile philosophy. The paper concludes with a discussion on future research efforts supporting the enabling agile development of hardware.