2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45489In models with a non-minimal Higgs sector, the lightest scalar state may be a neutral CP-even Higgs boson, whose properties are nearly identical to those of the minimal Higgs boson of the Standard Model. In such a scenario, the other Higgs scalars are significantly heavier than $m_Z$; their effects rapidly decouple from the low-energy theory. The decoupling limit of the most general CP-conserving two-Higgs doublet model is formulated. Detection of evidence for a non-minimal Higgs sector in the decoupling limit presents a formidable challenge for Higgs searches at future colliders.14 pages, PHYZZX macropackage, uses psfig for embedded figures, postscript file of the full manuscript available via anonymous ftp at ftp://scipp.ucsc.edu/pub/haber/bsmivheh.ps . Two postscript figure files (tahoefig1.ps and tahoefig2.ps) also available separately at the same locationHigh Energy Physics - Phenomenologytext