I will present cosmological results from the abundance and weak-lensing signal of redMaPPer clusters  as measured in the Sloan Digital Sky Survey (SDSS).  In this analysis we simultaneously fit for cosmological parameters and the richness--mass relation of the clusters.  Within a ΛCDM cosmological model with massive neutrinos, our results are consistent and competitive with that derived from cluster catalogues selected in different wavelengths.  Our result is also consistent with the combined probes analyses by the Dark Energy Survey (DES) and the Kilo-Degree Survey (KiDS), and with the Cosmic Microwave Background (CMB) anisotropies as measured by Planck. We demonstrate that the cosmological posteriors are robust against variation of the richness--mass relation model and to systematics associated with the calibration of the selection function.  In combination with Baryon Acoustic Oscillation (BAO) data and Big-Bang Nucleosynthesis (BBN) data (Cooke et al. 2016), we constrain the Hubble rate to be h=0.66±0.02, independent of the CMB.  Future work aimed at improving our understanding of the scatter of the richness--mass relation has the potential to significantly improve the precision of our cosmological posteriors.  The methods presented in this presentation were developed for use in the forthcoming analysis of cluster abundances in the DES.