Tim Howell is stepping down as the chief executive of post-trade giant Euroclear after six years at the helm.

Howell, who redefined the firm's business model by focusing heavily on IT and collateral management, will be replaced by Lieve Mostrey at the start of 2017. 

She was hired by Howell from BNP Paribas six years ago as the company's chief technology and services officer.

Now the largest international central securities depository in the world, Euroclear holds around €27.5trn of client assets.

Under Howell’s leadership, the company built its Collateral Highway platform which allows market participants to mobilse collateral across borders and time zones.

"The financial industry is attaching greater importance and value to effective collateral management," Howell wrote in Euroclear's annual report back in 2010.

He has also been instrumental in building up the firm's technology platforms and ensuring a financial turnaround following the crisis of 2008.

Euroclear reported a €280m net loss in 2010. Profit before tax in 2015 came in at €401m.

Meanwhile a successful migration to T2S, the securities settlement engine developed by the European Central Bank, recently occurred under Howell's watch.

Supporting clients with market change and exploring new technology, notably blockchain, will be areas of importance for Mostrey who served on the executive committee of BNP Paribas Fortis in Brussels before joining Euroclear in 2010.

Preparations for the implementation of Central Securities Depositories Regulation (CSDR) also remain a focus for Euroclear as does the expansion of fund services in emerging markets and improving the issuance and settlement of ETFs.

“The board thanks Tim for Euroclear’s success achieved during his tenure; building its business, forging new business partnerships, growing shareholder returns and strengthening the organisation’s resilience as a key financial market infrastructure,” said Marc Antoine Autheman, Euroclear's chairman. 

Commenting on her new role, Mostrey added: “As the financial industry’s trusted provider of post trade services, Euroclear is entering an exciting new phase of its development, amid the evolution of global capital markets. 

“I look forward to leading Euroclear’s team of dedicated employees, committed to delivering risk-mitigation, automation and efficiency at scale for our global client franchise.”