One primary characteristic of Alzheimer’s disease is neurofibrillary tangles made up of tau proteins that are not well understood. To test for the ratio in which tubulin and tau polymerize, microtubules were formed in vitro at varying concentrations. After separation by polyacrylamide gel electrophoresis, the amount of successful binding was measured using an IR scanner. Initial results showed that increasing the concentration of the 4RL tau isoform does not indefinitely increase the ratio in which the tubulin polymerizes. This suggests that there is competition among this isoform for binding space on the microtubules and past an ideal ratio the amount of additional polymerization dramatically falls. Contrarily, the shorter length 4RΔNΔC tau isoform was able to bind significantly more than the 4RL, and it continued to polymerize even at the highest concentration of tau that was tested. This is significant because determining the ideal binding ratios of tubulin and tau will help with understanding the situation where overabundance of the microtubule associated protein can begin to have adverse affects on the body.