| WP No | Workpackage Title | Active Partners (WP leader in bold) |
| WP1 | Novel methodologies for composite systems: implementation and control of composite clocks | INRIM, PTB, BEV-PTP, NPL, VTT, ISI, LUH, MPG, TU WIEN, UMK |
| WP2 | Composite clocks for improved stability | PTB, BEV-PTP, INRIM, NPL, CNR, ISI, LUH, TU WIEN |
| WP3 | Improved accuracy enabled by two species or two transitions | NPL, INRIM, PTB, VTT, ISI, LUH, MPG, UMK |
| WP4 | New reference transitions and quantum logic in mixed-species systems | LUH, PTB, BEV-PTP, ISI, MPG, TU WIEN |
| WP5 | Creating impact | VTT, PTB, BEV-PTP, INRIM, NPL, CNR, ISI, LUH, MPG, TU WIEN, UMK |
| WP6 | Management and coordination | PTB, BEV-PTP, INRIM, NPL, VTT, CNR, ISI, LUH, MPG, TU WIEN, UMK |
