As a new Nordita postdoc I would like to introduce myself and my research on the physics of the dusty and magnetized interstellar medium (ISM) in the Milky Way. The study of the ISM is key both for astrophysical processes in the local Universe, namely for star formation in the Galaxy, and for accurately probing the cosmic times, as the ISM is an unavoidable filter for primordial lights coming to us. The ISM is a mixture of cosmic rays, multi-phase gas, and dust particles, all coupled with magnetic fields. It is through their interactions that a complex, and still unclear, cycle leads diffuse/warm matter to condense into denser/colder regions, where stars eventually form. For decades, one difficult challenge of observational Astrophysics has been the characterization of magnetic fields along this evolutionary sequence. Today, thanks to the breakthrough of new experiments, such as the Planck satellite, we are now entering a new era to probe magnetic properties in the ISM. After reviewing the state-of-the-art investigation of magnetic fields in the Milky Way, in this talk I will give an overview of the recent results obtained by the Planck Consortium. Using unprecedented maps of linear polarization at sub-millimeter wavelengths, we traced the magnetic-field structure of our own Galaxy over the whole sky. I will present the data and focus on two main aspects: the role of magnetic fields in matter-structure formation from the diffuse ISM to the regions where star formation takes place; the impact of such ISM studies on high-precision cosmology stressing the synergy between the two fields.