  Combined ATLAS and CMS measurements of the Higgs boson production and decay
rates, as well as constraints on its couplings to vector bosons and fermions,
are presented. The combination is based on the analysis of five production
processes, namely gluon fusion, vector boson fusion, and associated production
with a $W$ or a $Z$ boson or a pair of top quarks, and of the six decay modes
$H \to ZZ, WW$, $\gamma\gamma, \tau\tau, bb$, and $\mu\mu$. All results are
reported assuming a value of 125.09 GeV for the Higgs boson mass, the result of
the combined measurement by the ATLAS and CMS experiments. The analysis uses
the CERN LHC proton--proton collision data recorded by the ATLAS and CMS
experiments in 2011 and 2012, corresponding to integrated luminosities per
experiment of approximately 5 fb$^{-1}$ at $\sqrt{s}=7$ TeV and 20 fb$^{-1}$ at
$\sqrt{s} = 8$ TeV. The Higgs boson production and decay rates measured by the
two experiments are combined within the context of three generic
parameterisations: two based on cross sections and branching fractions, and one
on ratios of coupling modifiers. Several interpretations of the measurements
with more model-dependent parameterisations are also given. The combined signal
yield relative to the Standard Model prediction is measured to be 1.09 $\pm$
0.11. The combined measurements lead to observed significances for the vector
boson fusion production process and for the $H \to \tau\tau$ decay of $5.4$ and
$5.5$ standard deviations, respectively. The data are consistent with the
Standard Model predictions for all parameterisations considered.
