Current and projected future oceans pose a range of multiple threats to marine organisms through altered environmental conditions that range from global- to local-scale processes. Here, I will explore how global change processes such as ocean heating and acidification are likely to affect marine invertebrates now and into the future, with a focus on tropical invertebrates. While increased temperature and ocean acidification affect life-history traits and physiology, elevated seawater carbon dioxide levels also alter behaviour in marine invertebrates across multiple trophic levels by interfering with a nerve receptor found throughout the animal kingdom. The alteration of key ecological behaviours could have flow on effects in ocean food webs as carbon dioxide levels increase. As marine invertebrates are a highly biodiverse group, focusing research on key representative species across taxa and assessing the most threatened groups are ways that may help achieve more impact or conservation in limited time. I will finish with science actions and initiatives that have helped me to stay positive (and avoid ecological grief where possible) when working on global change.