Abstract: A cross-protective influenza virus vaccine has been designed based on the incorporation of the genetically engineered, highly conserved M2 influenza viral protein optionally in combination with an adjuvant such as a bacterial flagellin protein incorporated into the membrane of a virosome or virus-like particles. Immunogenicity and the breadth of cross protection efficacy are significantly enhanced using multiple copies of the influenza M2 protein as a membrane bound tetramer and/or in combination with a membrane bound adjuvant. A method for vaccinating a subject for influenza A has also been developed that results in broad and improved cross-protection against multiple subtypes of influenza A virus.