  I review the status of large-scale structure studies based on redshift
surveys of galaxies and clusters of galaxies. In particular, I compare recent
results on the power spectrum and two-point correlation correlation function
from the 2dF and REFLEX surveys, highlighting the advantage of X-ray clusters
in the comparison to cosmological models, given their easy-to-understand mass
selection function. Unlike for galaxies, this allows the overall normalization
of the power spectrum to be measured directly from the data, providing an extra
constraint on the models. In the context of CDM models, both the shape and
amplitude of the REFLEX P(k) require, consistently, a low value for the mean
matter density $\Omega_M$. This shape is virtually indistinguishable from that
of the galaxy power spectrum measured by the 2dF survey, simply multiplied by a
constant cluster-galaxy bias factor. This consistency is remarkable for data
sets which use different tracers and are very different in terms of selection
function and observational biases. Similarly, the knowledge of the power
spectrum normalization yields naturally a value $b\simeq 1$ for the bias
parameter of $b_J$-selected (as in 2dF) galaxies, also in agreement with
independent estimates using higher-order clustering and CMB data. In the final
part, I briefly describe the measurements of the matter density parameter from
redshift space distortions in galaxy surveys, and show evidence for similar
streaming motions of clusters in the REFLEX redshift-space correlation function
$\xi(r_p,\pi)$. With no exception, this wealth of independent clustering
measurements point in a remarkably consistent way towards a low-density CDM
Universe with $\Omega_M\simeq 0.3$.
