According to Stella at Parties, Sarees and Melodies, 'Leader' was something of a transitional work for Naushad, representing a bridge between the classic, folk-based soundtracks of the 50s and earlier, and the modern jazz & beat based sounds of the 60s and beyond. And that it thus divided its audience. It's certainly worth attention though, with interesting going-ons on both sides of the divide.
'Tere Husn Ki' is a cheery duet with a lovely melody; 'Ek Shahinshah Ne Banavake' has the sort of psychedelic sounding sitar & violins vibe that George Harrison would later exploit (in a good way) with The Beatles; 'Mujhe Dunyawalo' is bouncy pop with a Latin tinge; 'Dayya Re Dayya' starts with a screaming trumpet followed by tribal percussion before heading off in all sorts of different musical directions; and more… so check it out.
1. Lata Mangeshkar & Mohd. Rafi: Tere Husn Ki
2. Lata Mangeshkar & Mohd. Rafi: Ek Shahinshah Ne Banavake
3. Mohd. Rafi: Mujhe Dunyawalo
4. Asha Bhosle & Mohd. Rafi: Ajkal Shauqe Deedar Hai
5. Asha Bhosle: Dayya Re Dayya
6. Lata Mangeshkar: Aj Hai Pyar Ka Faisla
7. Mohd. Rafi: Hameen Se Mohabbat
8. Mohd. Rafi & Chorus: Apni Aazadi Ko Ham