The introduction of two nucleophiles in the vicinal position of arenes via Sandmeyer‐type reactions is compromised by the problematic diazotization of ortho‐diaminoarenes. Herein, it is shown that vicinal substitution reactions are facilitated by the use of 1,2‐bis‐triazenylarenes. Two distinct methodologies for the synthesis of these triazenes are presented. The first approach involves the sequential conversion of 1‐amino‐2‐iodoarenes into first mono‐ and then bis‐triazenylarenes. The second procedure is based on Ru‐catalyzed [2 + 2 + 2] cycloaddition reactions between diynes and a 1,2‐bis‐triazenylalkyne. The two triazene groups in the products can be substituted sequentially by a range of nucleophiles including fluoride, chloride, bromide, iodide, azide, hydroxide, methoxide, and acetamide.