The current meningococcal polysaccharide vaccine is not effective in infants and children under two years of age. A new meningococcal vaccine, called a conjugate meningococcal vaccine, which can be used in infants and children under two years of age, is being tested. This vaccine links the capsular sugars to a protein carrier. This is the same method used for the conjugated Haemophilus influenzae type b and conjugated Streptococcus pneumoniae vaccines that are used as part of the recommended immunization schedule in infants and children in the United States. This step makes it possible to immunize infants beginning at two months of age because the protein-sugar complex is a more potent stimulus to the child’s immune system. Preliminary studies suggest that the conjugate vaccine will be highly effective. Studies are underway to evaluate the ability to combine this vaccine with other vaccines to decrease the number of injections that children receive. Research also is ongoing to develop a meningococcal vaccine that is effective in preventing disease due to serogroup B.