tradecraft
/ˈtreɪdkrɑːft/ /ˈtreɪdkraft/noun
1The art of practising a particular trade or profession; a person's skill in this.
2Specifically slang. The art of espionage and intelligence work; the skills and techniques involved in this.
3The art or skill of engaging in trading or commerce.
Origin
Early 19th century (in an earlier sense). From trade + craft.