This is a campaign that not only fought against child marriage, but successfully contributed to bringing about a change in the law that would protect girls from the harmful practise.

An important Pakistani cultural nuance to consider for the executional part of this campaign is the custom of receiving actual printed wedding invitations. This is a very popular cultural practise for weddings in Pakistan. Most of these are hand-delivered - failure to receive one is considered offensive.

This was our insight into the execution that led to us reaching lawmakers.

True change can only come with implementation of law, which lawmakers hold the key to. Our main objective, therefore, was to successfully reach lawmakers and get them to speak up further against child marriage in order to action a law.

A secondary objective for the campaign was to rather than spreading the message ourselves, turn the lawmakers into our ambassadors for the call against child marriage.

Pakistan has the 6th highest number of girls married before the age of 18 in the world. According to UNICEF, the country has nearly 19 million child brides. The UN children's agency estimates that around 4.6 million were married before the age of 15 and 18.9 million before they turned 18.

Across Pakistan, civil society has been at the forefront of fighting to end child marriage, pushing for tougher laws and working closely with communities, authorities and religious groups to change attitudes. What has been needed most to bring about true change, however, is a directive from the highest Islamic court in the country at a federal level that would say that 18 is the minimum age for marriage, a directive without which not much law changes.

To motivate lawmakers to pass a bill protecting children from child marriage, UN Women chose to target leaders with a direct mail campaign.

Members of the National Assembly of Pakistan received an invitation to a fictional child's wedding. Through a wedding card that would suit a child's wedding, designed entirely by children.

Rather than release a typical awareness campaign that would not generate any impact, we strategized that that our most effective way to help change the law would be to reach lawmakers directly, one-on-one, and to send them a personal motivational device.

We had to find a new mechanism to reach them, and our strategic insight was based around one particular cultural facet in Pakistan: the personal delivery of printed wedding cards inviting guests- the printed wedding card is so important even now that it is considered offensive to not receive one as an invite. Millions of colorful cards are printed every year that are delivered by hand or mail to guests.

We chose to follow a similar practise. The wedding, however, was that of a child bride. And so, of course, the invitation needed to reflect the same.

We invited dozens of young girls, ranging in age from 5 to 15, from all socio economic backgrounds, and allowed them to freely draw and sketch. One of the girls that contributed was an actual child bride.

We then took a number of the designs and sketches and combined them to form six chosen wedding cards, each reflecting a different area of the country, across all five provinces.

These were then dispatched directly to Members of the National Assembly, and other leaders and influencers in the country.

A short film explaining the idea accompanied with social posts was also launched.

We succeeded in reaching our target audience, receiving an almost immediate response from Members of Parliament, who chose to give statements holding the wedding cards, and asking other lawmakers to join them in the fight against child marriage.

Dozens of lawmakers joined our cause. In an actual parliamentary session at the National Assembly of Pakistan, leaders held up the Child Wedding Cards to demand a law be put into place to raise the minimum marriageable age to 18.

The lawmakers' efforts combined to raise conversation on the topic of child marriage in society and on air. The Federal Islamic court, the highest religious court in the country which activates common law, announced a landmark edict that 18 is applicable as the minimum age for marriage in Islam.

The work has already had a lasting impact by the kind of result it has generated. Once the federal religious body announced its verdict, the provincial law assemblies have now started to put into action their own state-wide regulations.

UN Women launches an initiative against child marriage every year. Now a legal verdict has been passed, our next plan is to focus on the implementation of the law.