For many users, the PI System is a mission-critical part of daily operations. High Availability (HA) for the PI Server and PI Asset Framework help achieve the necessary uptime. This talk will demonstrate recent enhancements that leverage PI SDK in PI Clients and PI Data Access products to buffer data when disconnected from the PI Server, as well as fan data when writing to an HA PI Collective. We will compare High Availability to similar technologies such as Microsoft Clustering (MSCS) and Virtualization. We will also discuss best practices and provide guidance for using these various tools to ensure your PI System is always available.