Clearly defined system boundaries are a prerequisite for effective risk assessments. Such risk assessments consider threats, vulnerabilities, likelihood, and impact to organizational operations, organizational assets, and individuals based on the operation and use of organizational systems. Risk assessments also consider risk from external parties (e.g., service providers, contractors operating systems on behalf of the organization, individuals accessing organizational systems, outsourcing entities). Risk assessments, either formal or informal, can be conducted at the organization level, the mission or business process level, or the system level, and at any phase in the system development life cycle.  [SP 800-30] provides guidance on conducting risk assessments.