Clue: 3.14 + 1 + 2.72, right? Initially simple for leaders (8)
Answer: PIONEERS
Explanation: Definition: leaders
**PI** ("3.14" – in maths, pi to 2 decimal places is 3.14) + **ONE** + **e** ("2.72" (in maths, "e", the base of the natural logarithm, is 2.72 to two decimal places) + **R** (right) + [initially] **S**(imple)