Majorana neutrinos and photinos from kaon decay

We discuss the suggestion by Deshpande and Eilam of putting bounds on the ${\nu }_{\tau }$ mass from the decay $K^{+}$→${\pi }^{+}$νν¯. We show that the Dirac or Majorana nature of the ${\nu }_{\tau }$ can make a significant difference in the pion energy spectrum. We also discuss the relative importance of the $K^{+}$→${\pi }^{+}$ ${\lambda }_{\gamma }$ ${\lambda }_{\gamma }$ mode, ${\lambda }_{\gamma }$ being the photino.