My issue is that entering play mode takes forever. I've been having this issue... I want to say since I upgraded to Unity 5, but I'm not actually sure because that was like two years ago. I have spent a lot of time just living with it because I had school projects I needed to do to graduate. Up to this point, I've updated Unity to the latest version as of today (5.6.1f1) and did a full reinstall, including clearing out any residual Unity references in my AppData folder (to the best of my ability). I also updated my graphics card drivers. For what it's worth, I've been running Unity on this computer for about 4 years now. Edit: I've also tried disabling my antivirus. I don't think the specs for my laptop are necessarily relevant, but here they are - it's an Alienware I got about four years ago, but it's still pretty good IMO: Windows 7 Processor: Intel i7-4700MQ CPU @ 2.40 GHz RAM: 16 GB GPU: Nvidia GeForce GTX 770M (Drivers are up to date as of earlier this week) I have an integrated graphics card and a GPU and I've made sure Unity's running on the GPU, most notably by making it run like even slower S*** on the integrated card. I can repro it in an empty project, so let's just talk about that. In a project I've just opened, when I go to enter Play Mode, it takes maybe 2-3 seconds. This is long, but not too big of a deal. In subsequent attempts, even if I immediately close and re-enter Play Mode, it will spike up to anywhere between 10-20 seconds. I have developed a game in these circumstances, but it sucks and I'd like to figure out how to fix it. So I pulled out the Unity Profiler and ran it on the editor. See the attached picture for what that looked like. So, I see that there's a major spike in EnterPlaymode -> ReloadAssemblies (18600 ms!). Here's the record of me entering and exiting Play Mode a few times, according to the engine log's time to reload assemblies: - Completed reload, in 3.189 seconds - Completed reload, in 15.761 seconds - Completed reload, in 16.191 seconds - Completed reload, in 14.970 seconds - Completed reload, in 14.906 seconds And I've done my research! Here's the most relevant stuff I could find on it: https://forum.unity3d.com/threads/r...-gets-exponentially-slower-and-slower.274452/ https://forum.unity3d.com/threads/speeding-up-monomanager-reloadassembly.274133/ http://answers.unity3d.com/questions/1195279/reload-assemblies-making-enterplaymode-take-long.html That last one doesn't even have an answer, haha. The other two are very symptomatically similar, with the long Reload Assemblies calls. However, those are both with BIG projects. Not projects that literally were just made with Unity. So, I'd love to go compress all my assets into asset bundles in my fuller projects, but I don't think it would actually help anything because I still get this problem in a project that has NO ASSETS. So that's why I'm here. Please help. Even if you guys can just tell me what Reload Assemblies is going through and doing, that might be helpful because maybe it's just paging? But that wouldn't explain the faster load time the first load in.