SCIM manages identity resources, while SAML exchanges security assertions for federation and SSO.
SCIM provides standardized schemas and HTTP operations for creating, reading, updating, deleting and searching users and groups. SAML carries XML-based authentication and attribute assertions between an identity provider and a relying service. A SaaS application may use SAML for sign-in and SCIM for account provisioning and deprovisioning; one does not replace the other.