Through their inhibition of immune regulatory pathways within the tumor microenvironment( TME ), checkpoint inhibitors represent an efficient treatment strategy for a number of cancers. Sadly, only a small percentage of cancer patients benefit clinically from immunotherapy, and the TME is starting to gain recognition as an important indicator of prognosis and treatment sensitivity. Within / across tumors, the degree and pattern of T-cell infiltration can differ significantly and represent a biological continuum. Along this continuum, three immune profiles have been identified: & lsquo, immune-department-and-resource-based, phenotype, active-active-increasing, inflamed-affection-related, and / or a-cell-associated, as well as the immune, hot – and racial, exaggerated, or hypnotic, respectively. Immune excluded is still the least well-defined of the three profiles, despite the fact that it is frequently linked to a lack of response to immune checkpoint inhibitors and subpar clinical outcomes. In order to address this, 16 multidisciplinary cancer specialists from all over the world were invited to take part in a three-round modified Delphi approach symposium. The first round consisted of an open-ended questionnaire sent via email, and the second round involved a face-to-face discussion of the results, allowing for statements to be updated as necessary to reach the rating committee’s maximum consensus( 75 % agreement ). The RC received the final round of questionnaire via email, and it was completely completed. Through the Delphi process, we were able to come to a consensus definition of immune exclusion that is applicable to many different cancer histologies and is both practical and clinically relevant. Five research priorities and a general understanding of the role of immune exclusion in checkpoint therapy resistance resulted from this process. Together, these tools might support efforts to address the underlying immune exclusion mechanisms that apply to all cancer types and, in the end, help with the creation of therapies that specifically target these mechanisms to enhance patient outcomes.