The Office of Management and Budget (OMB) issued new guidance to all federal agencies that acknowledges the need for federal employees to attend mission-related conferences and provides some best practices for approving travel and conference expenses. This new guidance adopts many of the best practices suggested in a meetings protocol that ASAE provided to OMB at its request.
The protocols state: "As each agency reviews its travel and conference-related activities, it is critical for each agency to continue to recognize the important role that mission-related travel and conferences can often play in Government operations. Given the unique travel and conference needs of each agency, there are circumstances in which physical collocation is necessary to complete the mission. These circumstances may include, but are not limited to, collaborations in the scientific community, unique training events for the law enforcement community, or the need to perform formal inspections as part of an agency's oversight and investigatory responsibilities."
While government attendance at conferences is likely to continue to be hampered by sequestration budget cuts, OMB has stated in clear fashion that federal agencies are encouraged to attend conferences that support their agency's mission. The OMB guidance can be found here