Arabic text
عَنْ أَنَسِ بْنِ مَالِكٍ رضي الله عنه قَالَ: قَالَ رَسُولُ اللهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «الدُّعَاءُ لاَ يُرَدُّ بَيْنَ الأَذَانِ وَالإِقَامَةِ».
Translation
Anas ibn Mālik (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) said: "Supplication between the Adhān (call to prayer) and the Iqāmah (second call to prayer) is not rejected."
Explanation
The Prophet (may Allah's peace and blessings be upon him) pointed out the merit of supplication between the Adhān and the Iqāmah and that it is not rejected and is worthy to be answered, so supplicate Allah during such a time.
Source: HadeethEnc.com