Alternative to NFS

Dear list readers, we have been extensively using NFS to export file systems to other computers. Since we are now in a phase of reauditing our network for security, be are searching for an alternative to that very insecure and part-time even instable protocol. Do you have any advice on which system to use? It should contain at least the same amount of features lacking all the possible security holes. Kind regards, A. Achtzehn