The term renzuru (連鶴, "conjoined cranes") refers to an origami technique whereby one folds multiple cranes from a single sheet of paper (usually square), employing a number of strategic cuts to form a mosaic of semi-detached smaller squares from the original large square paper. The resulting cranes are attached to one another (e.g., at the tips of the beaks, wings, or tails) or at the tip of the body (e.g., a baby crane sitting on its mother's back). The trick is to fold all the cranes without breaking the small paper bridges that attach them to one another or, in some cases, to effectively conceal extra paper. This origami technique was first illustrated in one of the oldest known origami books titled Hiden Senbazuru Orikata (Secret of folding 1,000 Cranes ), published by Roko-an in 1797.
After having perfected this technique, Linda discovered how to turn the cranes into a 3-dimensional shape. Her discovery was the Peace Sphere, a sculpture of 18 cranes, all attached and folded from a single sheet of paper. This led to other 3-dimensional shapes such as the Crane Cube, the Crane Pyramid, and the Sphere Within a Sphere.
Linda continues to discover additional shapes, such as the Past, Present and Future Crane Star which adorns the top of the World Tree of Hope, the world's largest origami tree. This tree appears during the holidays in San Francisco and is completely covered in thousands of origami cranes and stars.