The level structure of 169Yb and the nature of the linking transitions have been studied by radioactive decay of 169Lu polarised at low temperatures in a gadolinium host. Anisotropies of 112 gamma rays in 169Yb have been measured. Unambiguous spin assignments have been made for a number of levels below 2 MeV and multipole mixing ratios of about 90 transitions have been deduced. In particular, it has been found that the 1070.8 keV 7/2+ to 7/2+ transition has delta =0.74-0.13+0.11 or 10.3-4.5+50.1 and from the experimental alpha K value an E0:E2 mixing ratio of mod q mod =5.8+or-0.8 or 3.55+or-0.16, respectively, has been obtained. The energy and structure of individual levels, reduced E2 and M1 transition probabilities and E2:M1 mixing ratios have been calculated using the quasiparticle-phonon model including a Coriolis interaction. In general, good agreement is obtained between the theoretical predictions and the experimental results.