The large differences in chemical shifts that result from oxygen's being incorporated into the polymer backbone yield more accurate qualitative and quantitative analysis through NMR than those polymers that do not have oxygen in the backbone. Configuration effects are observed without interference from methylene groups that frequently interfere in the analysis of polymers. However, the results obtained on polyacetaldehyde with the new 200-MHz Varian Instrument at ambient temperature show a much more complete definition of the configuration than can be obtained with lower-frequency instruments. They show that there are more isotactic triads than syndiotactic triads for the methyl group in “atactic” polyacetaldehyde and that this polyacetaldehyde is nearly a random polymer. By means of the new 220-MHz Varian Instrument and heating of the samples to elevated temperatures for better-resolved lines complete configurational analysis of polyacetaldehyde should become possible.