While recent years have seen great advances in the generation, detection, and application of terahertz frequency radiation, this region of the electromagnetic spectrum still suffers from a lack of efficient and effective frequency specific optical components. While such terahertz devices do exist, they are often limited by the materials they are based on and a lack of frequency selectivity and tunability. Metamaterial devices can provide frequency resonant behavior in the form of transmissive and reflective filters. Such a frequency selective surface can also be made tunable via the use of a flexible substrate. In this talk, we will highlight work involving the design, fabrication, and characterization of terahertz metamaterial devices based on flexible substrates. Finite element method simulations have been utilized to design a split-ring resonator (SRR) structure on a flexible SU8 polymer substrate with a targeted 250 GHz resonant response. Multiple configurations of SRR arrays have been fabricated on free standing SU8 substrates. These devices have subsequently been characterized using terahertz time-domain spectroscopy and imaging systems. The metamaterial devices have shown selective transmission and reflection over a narrow range of frequencies near the targeted resonance at 250 GHz. Details of both the design, fabrication, and characterization will be discussed.