Permissions can be delegated to enable access to resources associated with one or more different accounts, which might be associated with one or more different entities. Delegation profiles are established that are associated with at least one secured account of at least one customer. Each delegation profile includes information such as a name, a validation policy that specifies principals which may be external to the account and which are permitted to assume the delegation profile, and an authorization policy that indicates the permitted actions within the account for those principals which are acting within the delegation profile. Once a delegation profile is created, the profile can be available for external principals or services that provide a user credential delegated access under the account, where that credential is provided by a trusted identity service. Access can be provided across accounts using the user credential.