A study of the experimental systematics of elementary-particle lifetimes leads to the following conclusions: (a) Elementary-particle lifetimes $\tau$ divide empirically into two distinct groups—"particles" ($\tau >{10}^{-21\mathrm{}}$ sec) and "resonances" ($\tau <{10}^{-22\mathrm{}}$ sec), where "particle" lifetimes are spaced by powers of $\alpha =\frac{e^2}{\hslash c}$ and "resonance" lifetimes occur as a continuum of values; (b) the scaling of "particle" lifetimes in powers of $\alpha$ is a "lifetime democracy" in the sense that baryons, mesons, and leptons are all grouped together in one over-all lifetime scaling pattern; (c) integral-spin boson "particle" lifetimes scale in powers of $\alpha$, whereas half-integral-spin fermion "particle" lifetimes scale in powers of ${\alpha }^2$; (d) an SU(3) grouping of lifetimes reveals some striking patterns, with the $\psi$ and ${\psi }^{\prime }$ lifetimes appearing as an extension of one of these patterns; (e) phase-space corrections, which are important for "resonance" lifetimes, are not as important for "particle" lifetimes; (f) if hadron lifetimes are grouped according to baryon number and strangeness, and then sorted into spin states, an empirical spin and lifetime correlation is seen in all of these groups: As the spin value increases, the maximum observed lifetime decreases.

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