The paper by Shaffique Adam, E. H. Hwang, V. M. Galitski, and S. Das Sarma provides a self-consistent theoretical framework to explain the transport properties of graphene sheets at zero magnetic field, focusing on the role of charged impurities. They find that the observed transport properties, particularly the minimum conductivity, are not universal but depend on the concentration of charged impurities. For dirty samples, the minimum conductivity is indeed $4e^2/h$, while for cleaner samples, it increases to $8e^2/h$ for impurity concentrations around $20 \times 10^{10} \text{cm}^{-2}$. The authors argue that improving graphene mobility can be achieved by eliminating charged impurities or using a substrate with a higher dielectric constant. The theory is based on a self-consistent RPA-Boltzmann formalism, which accounts for the screening of charged impurities and the resulting electron-hole puddles, providing a physically appealing explanation for the observed transport data. This work addresses a key puzzle in graphene transport and offers insights into how to enhance graphene's technological potential.The paper by Shaffique Adam, E. H. Hwang, V. M. Galitski, and S. Das Sarma provides a self-consistent theoretical framework to explain the transport properties of graphene sheets at zero magnetic field, focusing on the role of charged impurities. They find that the observed transport properties, particularly the minimum conductivity, are not universal but depend on the concentration of charged impurities. For dirty samples, the minimum conductivity is indeed $4e^2/h$, while for cleaner samples, it increases to $8e^2/h$ for impurity concentrations around $20 \times 10^{10} \text{cm}^{-2}$. The authors argue that improving graphene mobility can be achieved by eliminating charged impurities or using a substrate with a higher dielectric constant. The theory is based on a self-consistent RPA-Boltzmann formalism, which accounts for the screening of charged impurities and the resulting electron-hole puddles, providing a physically appealing explanation for the observed transport data. This work addresses a key puzzle in graphene transport and offers insights into how to enhance graphene's technological potential.