The perpendicular and parallel magnetic transitions for pure Pb films and foils have been determined from transverse magnetization and ac susceptibility measurements as a function of thickness (400 \AA{} to 35 \ensuremath{\mu}) and temperature (1.4 to 4.2\ifmmode^\circ\else\textdegree\fi{}K). The perpendicular critical field (${H}_{\ensuremath{\perp}}$) for thicknesses less than a critical thickness, ${d}_{c}\ensuremath{\approx}15$ k\AA{}, is in good agreement with the theory of Tinkham if it is assumed that the penetration depth is thickness-dependent. The data for thicknesses above ${d}_{c}$ follow a thickness dependence predicted from the effect of a positive surface energy on the free energy of the intermediate state. At ${d}_{c}$ there is a minimum in ${H}_{\ensuremath{\perp}}$. The parallel critical field (${H}_{\ensuremath{\parallel}}$) up to ${d}_{c}$ is in good agreement with the theory of Saint James and de Gennes for a second-order transition. Above ${d}_{c}$, ${H}_{\ensuremath{\parallel}}$ agrees with the bulk value of ${H}_{c3}$ for lead. In the vicinity of ${d}_{c}$ the magnetization curve starts to exhibit a reversible tail which persists to larger thicknesses and whose slope is in reasonable agreement with theory. From the data, the bulk values of $\ensuremath{\kappa}(T)$, $\ensuremath{\lambda}(T)$, ${\ensuremath{\lambda}}_{L}(0)$, and ${\ensuremath{\xi}}_{0}$, as well as the thickness dependence of these quantities, have been computed.