contamination than previously believed. This conclusion provides strong 
support for lowering the levels of containment required not only for work 
on primates but in other situations as well. 
In conclusion, the adoption of these new guidelines coupled with a 
continuing program of risk assessment will make possible the rapid advance- 
ment of scientific knowledge under containment conditions consistent with 
possible risk. 
Norman Arnheim 
Associate Professor of Biochemistry 
NA/bd 
[A-143] 
