In search of newer and potent antitubercular agents, a series of phenothiazine derivatives were evaluated for antitubercular activity. This study may prove to be helpful in development and optimization of existing antitubercular activity of this class of compounds.Quaternized chlorpromazine, triflupromazine, and promethazine derivatives were tested as antitubercular agents against both actively growing and non-replicating Mycobacterium tuberculosis H37Rv. A slight variation in the substitution pattern on the phenothiazine nucleus often causes a marked difference in activities and therefore phenothiazines with various substituents are being synthesized and tested for activities in search of better medicinal agents.