We have made some slight revisions to the NABs which support the Access 2 Science Units. These Units were revised in 2003 to reduce the amount of evidence required to three experiments and three sources of handling information for each Unit. However, there still seemed to be some ambiguity over evidence requirements stated in the NABs. We have now amended the NABs to remove this ambiguity and to ensure they are consistent with the requirements stated in the Units. The revised NABs are now available on SQA's secure website. Please approach your centre's SQA Co-ordinator for access.