The changes in the economy and society in this century have placed a greater emphasis on the skills that citizens need to be successful. This diverse set of skills, often referred to as 21st century skills, and including critical thinking, creativity, problem solving, communication, and socio-emotional skills, among others, are in high demand as the need for rote or routine-based knowledge decreases due to automation in the workplace (Rotherham & Willingham, 2010). In education specifically, there is the concern of a global learning crisis--that students are not fully prepared with the skills they need to thrive in today's rapidly changing world (The Education Commission, 2017). With the learning goals of education shifting to include a broader range of skills, the challenge globally is how to support students in developing these skills. The components of the education system must be aligned to support the development of 21st century skills, and the qualitatively different structure of these skills requires some completely new approaches, both in the measurement aspect and collection of assessment data. A major issue that confronts education systems is a deficiency in the effective use of collected student learning outcomes data. Notwithstanding the huge sums that are dedicated to its collection, a proportional commitment is not made to its strategic analysis or its dissemination. The main purpose of this publication is to provide guidance on how data from 21st century skills assessment can be used and interpreted in terms of learning outcomes to inform teaching and learning. Towards this purpose, the authors put forward actionable recommendations that are both applicable and relevant to the current state of assessing these 21st century skills to enhance learning outcomes, as well as forward-looking in anticipating the future of assessment. In this publication, the authors consider the purposes of collecting student achievement data associated with 21st century skills, discuss how these data are currently used in various contexts and the challenges associated with each, and finally provide key principles for effective data use both generally and specific to major stakeholders. [Support was provided by Porticus.]