Title: Orthonormal Completion of an array of Unit Length Vectors Abstract: Some interesting new results on orthogonality, and their contribution to the slowly developing understanding of a class of very useful numerical algorithms which have very strange numerical behaviours. These include Modified Gram-Schmidt (MGS) for orthogonalization and linear least squares problems, MGS-GMRES for solution of large sparse systems of equations, the Conjugate Gradients Method for that problem and for optimization, Lanczos' tridiagonalization of a matrix for the eigenproblem, the Golub-Kahan bidiagonalization for many classes of problem, and some other crucial algorithms for large sparse matrix problems.