This study presents the share of 5 most productive South African institutions for the main stream scientific out put covering the 10 year periods of 1995-2004. This paper discusses the distribution of publications by institutions, Index of specialization, collaboration and pattern of co-authorship. The result shows that South African authors collaborate more frequently with international authors with a percentage of (73.99%) than did so for national collaboration which amount to (26.01%). This was confirmed statistically at the confidence level of P-value 0.025. A further non-parametric chi-square statistical analysis illustrated that there are significant differences in the proportion of co-authorship among the 5 institutions (p-value0.005)
