This research memorandum highlights the collaborative efforts of the numeracy panel for the ETS Return on Investment (ROI) Study, Phase 1, comprising David Tout, Kees Hoogland, and Javier Díez-Palomar, in developing their research memorandum, "Improving the Quality of Numeracy Skills: Progressing from Level 2 to Level 4 on the PIAAC Cycle 2 Proficiency Scale." This memorandum captures the expert opinions of the panel sessions. It is provided as supporting documentation for the policy report, "Level Up: Raising the Skills of Adults in the United States and Other Countries."