We are in the process of obtaining and analysing VLBA polarisation data for the 191 Active Galactic Nuclei (AGNs) in the MOJAVE-II sample at 5.0, 2.3, 1.7 and 1.4 GHz (6, 13, 18, 21 cm) obtained in Summer 2017 -
Spring 2018. This is the first set of simultaneous observations in this frequency range for a large sample of AGNs, and will enable studies of the evolution of the intensity and magnetic-field structures of these AGN jets
as they propagate from parsec to kiloparsec scales. This frequency range was chosen especially to enable sensitive and detailed spectral and Faraday-rotation mapping on scales out to tens to hundreds of parsec from the core at the typical distances of AGNs. The individual-pixel uncertainties in the Faraday rotation measure provided by these observations are typically less than 2-3~rad/m^2 - about a factor of 3-5 lower than
1.4-1.7 GHz RM images and a factor of 50-100 lower than 8-15 GHz RM images previously published in the framework of the MOJAVE project. Some first results from this new project are presented, highlighting the high sensitivity
of the data to intensity, polarization and Faraday
rotation on a wide range of scales.