Integrating Autotuning Into the Application Development Environment Bill Gropp Applications programs must often trade between portability and performance because of the complexity of tuning codes for particular architectures and inputs. In addition, even when portability is not an issue, achieving high performance, even for relatively simple operations such as dense matrix-matrix multiply, often requires very complex code (relative to the straightforward code that functionally describes the operation). Autotuning tools offer the promise of a practical mechanism for creating that complex code. However, to be truly successful, these tools (and the plural is essential) must be smoothly integrated into the applications development environment. This talk will discuss some of the needs of applications and illustrate some possible approaches for building an environment will allow autotuning tools to flourish.