As of 2015, Super Anti-Spyware, Lavasoft AdAware and Spybot Search & Destroy are the top-rated standalone anti-spyware products, according to TechRadar. Webroot Spy Sweeper, Trend Micro HijackThis, Macafee Anti-Spyware and Windows Defender are highly rated anti-spyware programs that come with anti-virus software suites.
General anti-malware software scans for adware and spyware. MalwareBytes Anti-Malware is a top-rated program that removes spyware, but does not focus on spyware specifically.
About.com's Internet Expert recommends running more than one anti-spyware program to provide maximum protection. It is safe to run more than one standalone anti-spyware or anti-malware program, but it is only possible to safely run a single full anti-virus suite at one time. Full security suites such as Webroot and McAfee should never run together.