OBJECTIVES: The impact of health economics and outcomes research (HEOR) evidence on reimbursement decisions is known and explicit in many major markets, but in the U.S. skepticism regarding the impact of such evidence on payer decision-making remains.  Despite this, strategic and tactical support from HEOR units in pharmaceutical companies is believed to have a substantial impact on the success of a product, as evidenced by continued and increasing investment in HEOR.  We sought to understand, from a pharmaceutical manufacturer’s perspective, how the decision to invest in HEOR is made and how such evidence is believed to influence reimbursement and market access in the U.S.  METHODS: We conducted two focus group sessions followed by an online stated choice survey with HEOR representatives from various pharmaceutical companies.  Focus group sessions were centered on the scope of work conducted by HEOR units and how investment decisions are made.  We subsequently developed and administered a survey that presented the HEOR representatives with 20 target product profiles and asked respondents to rate the perceived value that HEOR evidence would have on reimbursement decisions for each product and to identify the types of HEOR evidence that would be most useful for payers. RESULTS: We identified eight types of HEOR evidence that are used to inform reimbursement decisions.  Seven product attributes, four market attributes, three data quality attributes, and seven exogenous factors were identified as factors in the decision to invest in HEOR.  We report the most influential factors and trends in the types of evidence pursued. CONCLUSIONS: This more nuanced understanding of the drivers of private HEOR investment and perceived value to payers will assist companies in planning future investments.  These hypotheses will be evaluated with payers to assess the sensitivity of their decisions to HEOR evidence under specific product and market scenarios.