We argue that an extension of the minimal supersymmetric standard model (MSSM) that gives rise to viable thermal inflation, and so does not suffer from a Polonyi or moduli problem, should contain right-handed neutrinos which acquire their masses due to the vacuum expectation value of the flaton that drives thermal inflation. This strongly disfavors SO(10) grand unified theories. The {mu} term of the MSSM should also arise due to the VEV of the flaton. With the extra assumption that {ital m}{sup 2}{sub {ital L}}{minus}{ital m}{sub {ital H}{sub {ital u}}}{sup 2}{lt}0, but, of course, {ital m}{sup 2}{sub {ital L}}{minus}{ital m}{sub {ital H}{sub {ital u}}}{sup 2}+{vert_bar}{mu}{vert_bar}{sup 2}{gt}0, we show that a complicated Affleck-Dine-type baryogenesis employing an {ital LH}{sub {ital u}} {ital D}-flat direction can naturally generate the baryon asymmetry of the Universe. {copyright} {ital 1996 The American Physical Society.}