2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48489We review the B meson lifetime problems and nonspectator effects. The predictions of B meson lifetime ratios depend on four unknown hadronic parameters $B_1$, $B_2$, $ε_1$ and $ε_2$, where $B_1$ and $B_2$ parametrize the matrix elements of color singlet-singlet four-quark operators and $ε_1$ and $ε_2$ the matrix elements of color octet-octet operators. To understand contributions of the nonspectator effects to the B meson lifetime ratios, we derive the renormalization-group improved QCD sum rules for these parameters within the framework of heavy quark effective theory.12 pages, 2 figures, talk presented at the 11th Summer School and Symposium on Nuclear Physics (NuSS'98), "Effective Theories of Matter", Seoul National University, June 23--26, 1998High Energy Physics - Phenomenologytext