Lego Ideas was first introduced as an offshoot of the Japanese website Cuusoo, minecraft ideas for building as a collaboration between that company and The Lego Group. Titled Lego Cuusoo, the site was labeled a beta site and remained so until the unveiling of Lego Ideas as a finished product.

17 is the Apollo 11 Saturn V rocket, and contains 1969 pieces, the same year as the first moon landing. Users express their idea by combining a written description of the idea and a sample Lego model that demonstrates the concept into a project page. Once the page is published it is viewable to other users. The goal of every project is to be supported by 10,000 different users, which would then make the project eligible for review. Originally, project submissions were allowed to be about anything and had no limits on the size and style of project. After sets began to be rejected with stated reasons, Lego Ideas announced restrictions on content including the use of no new part molds, banning intellectual properties owned by competing toy companies, and adult content. All eligible projects are collectively reviewed in the order of whichever projects hit 10,000 supporters within any of the three tri-annual deadlines of May, September, or January.

Due to the increasing number of project submissions based on ideas that the Lego Company would reject, Lego Ideas has refined its submission standards over the years. Since its inception, a number of sets that have reached the 10,000 vote threshold have been rejected during the review for various reasons. Some rejected sets have been based on specific intellectual properties were rejected due to the content matter presented. Anything which contains alcohol, sex, drugs, religious references, post-World War II warfare or based on a first-person shooter is deemed inappropriate for younger Lego fans. In the first 2015 review, announced in October 2015, no projects were selected for the first time as the many projects were rejected for various reasons.

Many of these projects would not have met the revised submission standards issued in June 2016. If the product is cleared for production, it is developed and later released as an official set under the «Lego Ideas» banner. Sets are listed in order of announcement. Bold line indicates when branding changed from Cuusoo to Ideas. Flags represent the creators country of origin. First announced Cuusoo set to be internationally available.

Based on the video game Minecraft. First set to start a new Lego theme Lego Minecraft. Lego also used this license for character and level packs in the Lego Dimensions toys-to-life video game. Based on the NASA Mars Curiosity Rover. Based on the Ecto-1 from the Ghostbusters franchise.

Based on the TV series The Big Bang Theory. Based on the Pixar film WALL-E. WALL-E but took longer gain approval. Based on the BBC TV series Doctor Who.

A Labyrinth marble game puzzle built from Lego bricks. Based on the classic British sports car. Based on the animated series Adventure Time. Based on the animated film Yellow Submarine. Based on the rocket used for NASA’s Apollo 11 moon mission. Based on accomplished women who have worked for NASA. A Ship in a bottle built from Lego bricks.