Electronic Journal of Differential Equations, Conference 05 (2000), pp. 311-322. Title: Instability and exact multiplicity of solutions of semilinear equations. Authors: Philip Korman (Univ. of Cincinnati, Cincinnati, OH, USA) Junping Shi (College of William and Mary, Williamsburg, VA, USA) Abstract: For a class of two-point boundary-value problems we use bifurcation theory to show that a solution is unstable under a simple, geometric in nature, assumption on the non-linear term. As an application we obtain some new exact multiplicity results. Published October 24, 2000. Math Subject Classifications: 34B15. Key Words: Bifurcation of solutions; global solution curve.