If you're interested in politics, you see the symbol 協 quite a lot, in both Japanese and Chinese.
In Japanese, 協 is a rare example of a character in common use that has just one sound (consistently): kyō (きょう).
Kyō is supposedly the on-yomi (音読, Chinese-derived pronunciation) for both 協 and 共, two words with closely related meanings that --naturally-- sound completely different in modern Chinese (協 xié, vs. 共 gòng). 共同 and 協同 are now treated as two different ways of "spelling" the same word (きょうどう). I'm left wondering if the sound is really derived from the Chinese precedent, or if the meaning and sound were instead primary, and then applied to both 協 and 共 characters, a pattern known as jukujikun, 熟字訓.
Etymologically, the radical on the left hand side of 協 looks like an awkward addition to the character, and it is. Your dictionary may still have an entry for the antiquated version (without the 十), writ 劦.
Although many, many characters are categorized as including the "ten" radical (十) in some abstract form, there are few glyphs that really have it as a free-standing figure (on the left or the right) in traditional Chinese: 什, shén; 計, jì; 針, zhēn; 汁, zhī. The 十 appears, also, in some of my least favorite examples of character simplification, such as the reduction of 葉 to 叶 (yè, "leaf").
Here's the twist in the plot: this symbol 叶 was used --in ancient times, according to the Shuo Wen [說文解字]-- as a shorthand variant for 協 in Chinese (i.e., long before the 20th century reforms that reassigned the meaning of 叶 from "harmony" to "leaf"). The incoherent addition of 十 to the left side of 劦 may have been to clarify that 協 meant the same 劦 known as 叶 (i.e., to further associate the two characters by giving them the same radical). Sadly, the modern changes in the language are just as incoherent as the ancient ones, with the transformation of 葉 into 叶 being an excellent (and depressing) example.
