Portable and effcient ways for calling numerical high performance software libraries from HPF programs are investigated. The methods suggested utilize HPF’s EXTRINSIC mechanism and are independent of implementation details of HPF compilers. Two prototypical examples are used to illustrate these techniques. Highly optimized Blas routines are utilized for local computations: (i) in parallel multiplication of matrices, and (ii) in parallel Cholesky factorization. Both implementations turn out to be very efficient and show significant improvements over standard HPF implementations.