Session management is the process of maintaining stateful information across multiple HTTP requests. In ASP.NET MVC, there are several techniques that can be used to manage sessions. One approach is to use built-in session state management provided by the HttpSessionState class. This allows developers to store and retrieve data from the HttpSessionState object using the Session property.

Another approach is to use TempData, which is a type of session state management that is specific to ASP.NET MVC. TempData allows developers to store data that will be available only for the next request. This can be useful for scenarios where data needs to be transferred between actions or controllers.

In addition to these built-in approaches, ASP.NET MVC also supports third-party session management tools such as Redis and Memcached. These tools can be used to store session data in a distributed cache, which can help to improve scalability and performance in web applications.

To implement session management in ASP.NET MVC, developers should first determine what type of data needs to be stored in session and for how long. They should also consider the security implications of storing sensitive information in session, such as user credentials or credit card information. Developers can then choose the appropriate session management technique based on their requirements and implement it using the appropriate API or tool.

Finally, it's important to test and debug session management functionality to ensure that it's working as expected. This may involve using tools like Fiddler or Chrome Developer Tools to inspect HTTP requests and responses, as well as testing for edge cases like concurrent user sessions and session timeouts. By following best practices and testing thoroughly, developers can ensure that their ASP.NET MVC applications have robust and reliable session management capabilities.