A new technique for interactive vector field visualization using large numbers of properly illuminated stream lines is presented. Taking into account ambient, diffuse, and specular reflection terms as well as transparency, we employ a realistic shading model which significantly increases quality and realism of the resulting images. While many graphics workstation offer hardware support for illuminating surface. Primitives, usually no means for an accurate shading of line primitives are provided. However, we show that proper illumination of lines can be implemented by exploiting the texture mapping capabilities of modern graphics hardware. In this way high rendering performance with interactive frame rates can be achieved. We apply the technique to render large numbers of integral curves in a vector field. The impression of the resulting images can be further improved by making the curves partially transparent. We also describe methods for controlling the distribution of stream lines in space. These methods enable us to use illuminated stream lines within an interactive visualization environment. © 2006-2014 Asian Research Publishing Network (ARPN).