  We explore analytically how does the Standard Model emerge as the quantum low
energy effective theory of the Minimal Supersymmetric Standard Model (MSSM) in
the decoupling limit where the sparticles are much heavier than the electroweak
scale. In this work we integrate the sfermions to one-loop and compute their
contributions to the effective action for standard electroweak gauge bosons. A
proof of decoupling of sfermions is performed by analyzing the resulting
effective action in the asymptotic limit $m_{\tilde f} \gg m_z$. A discussion
on how the decoupling takes place in terms of both the sparticle physical
masses and the non-physical MSSM parameters is included.
