A balanced cyberinfrastructure is necessary to meet growing data-intensitive scientific needs. We believe that available resources should be allocated to benefit the broadest cross-section of the scientific community. Given the power-law distribution of problem sizes, this means that about half of funding agency resources should be spent on tier-1 centers at the petascale level and the other half dedicated to tier-2 and tier-3 centers on a cost-sharing basis. Funding agencies should support balanced systems, not just CPU farms, as well as petascale IO and networking. They should also allocate resources for a balanced tier-1 through tier-3 cyberinfrastructure.