  We prove a Model Existence Theorem for a fully infinitary logic for metric structures. This result is based on a generalization of the notions of approximate formulas and approximate truth in normed structures introduced by Henson and studied in different forms by Anderson and Fajardo & Keisler. This theorem extends Henson's Compactness Theorem for approximate truth in normed space structures to infinitary formulas. 
A Model Existence Theorem for Infinitary Formulas in Metric Spaces