The May 2006 issue of Microbe contained a letter from John S. Hibbard in which he presented a cogent case stating that “….all infectious diseases should be treated with a combination of two antibiotics with different mechanisms of action…” His premise is a good one, but is 46 years too late. It's been done! I refer him to: (i) W. E. Herrell, A. Balows, and J. Becker. Erythrocillin: a new approach to the problem of antibiotic resistant staphylococcus. J. Antibiot. Med. Clin. Ther. 7:637–640,1960; (ii) W. E. Herrell, A. Balows, and J. Becker. Alpha phenoxypropyl penicillin & propionyl erythromycin against resistant staphylococci, Antimicrob. Agents Chemother. 1961:723–733, 1962; (iii) W. E. Herrell, A. Balows, and J. Becker. Bacterial effect of the combination of Cephalothin & Streptomycin against Strep. viridans. Antimicrob. Agents Chemother. 1964:350–354, 1965. In each of the above publications we provided data to show that the effect of the combined antibiotics in serum attainable levels was bactericidal as opposed to the ineffectiveness of the maximum dosage of each antibiotic when given singly.