Abstract. To handle signal processing algorithms such as the Fast Fourrier Transform (FFT) or the Discrete Cosine Transform (DCT) system designers have traditionally resorted to specialized hardware with builtin vector-processing capabilities. With the advent of the Altivec vector extensions for the general-purpose PowerPC processor, developers have the ability to write efficient signal processing code in C and C++. Using Altivec-enabled PowerPCs as an example, this paper explains what can and should be done to write not only efficient, but also clean and reliable vector processing code in Ada.