The 2017 Tax Cuts and Jobs Act (TCJA) brought significant changes to how research and experimentation expenses are taxed. Previously, taxpayers had the choice to deduct these expenses in the year they incurred them or spread them out over time. However, the TCJA removed this choice in many cases, starting in 2022. This change has caused uncertainty among taxpayers and tax professionals. In response, the IRS issued preliminary guidance in early 2022, followed by Notice 2023-63 in September, which serves as their final guidance before proposing a rule to implement TCJA's changes. Compliance with these guidelines is voluntary, as they were released shortly before the extended filing deadline for many 2022 tax returns. This article offers an overview of TCJA's changes and the IRS's guidance.