| 2002 – 2010 | SILENT WITNESS | Leo Dalton | Jessica Pope | BBC (9 series) | |
| 2002 | SPOOKS | Victor Ellis | Rob Bailey | Kudos Productions | |
| 2002 | THE RALF LITTLE SHOW | The Father | Mario Sylianides | BBC | |
| 2001 | THE GIST | Philip | John Morton | BBC | |
| 2000/1 | ATTACHMENTS | Will | Simon Heath | World Productions (2 series) | |
| 2001 | PEOPLE LIKE US: THE PILOT | Nigel | Paul Schlesinger | BBC | |
| 2000 | THE LAW | Vine | Juliet May | Pearson TV | |
| 1999 | HOPE & GLORY | Colin | Juliet May | BBC | |
| 1998 | THE BROKER’S MAN | Superintendent Staples | Moira Armstrong | Bentley Productions | |
| 1996 | THE RAG NYMPH | Mr Quinton | David Wheatley | Festival Films | |
| 1996 | DANGERFIELD | Davidson | Rob Walker | BBC | |
| 1996 | THE BILL | Dr Perry | Peter Duffell | Thames | |
| 1993 | A DARK ADAPTED EYE | Andrew | Tim Fywell | BBC | |
| 1992 | CRIME FILE: THE ROSE MURDER | Mr Rose | Nigel McRery | BBC | |
| 1991 | THE HOUSE OF ELIOTT | Robert Adams | Rodney Bennett | BBC (series regular) | |
| 1991 | THE BILL | Inspector Bruce | Mike Vardy | Thames | |
| 1991 | THE SOUTH BANK SHOW: JULIAN BARNES | Hilary Chadwick | LWT | ||
| 1990 | SOLDIER, SOLDIER | Bird | Zelda Barron | Central Films | |
| 1990 | SHOPPING AROUND | Robin Carr | LWT | ||
| 1989/92 | CASUALTY | Dr Andrew Bower | various | BBC (series regular) | |
| 1988 | CONTRASTS | Lord Byron | Central TV | ||
| 1987 | BULMAN | Bruce McDonald | Granada | ||
| 1986 | DEAD LUCKY | Tim | Barbara Rennie | BBC | |
| THE MISTRESS | BBC | ||||
| BULMAN | Willie Bruce | Granada | |||
| CITY SUGAR | Leonard Brazil | RTV (Hong Kong) |
| LEAVE TO REMAIN | Les Blair | Spellbound Films | |||
| COMRADES | James Lovelace | Bill Douglas | Skreba & Greenpoint | *Winner of the London Film Festival Award | |
| PARADISE POSTPONED | Alvin Rakoff | Euston Films |
William began his career playing seasons at Worcester and York Reps, for the Bubble Theatre and for the Chung Ying Theatre of Hong Kong, a half Chinese/half British company based in Hong Kong. Parts during this time included:
| HAPPY END | Sammy Wurlitzer | Bob Carlton | |||
| ONE NIGHT STAND | Damien | Mike Harding | |||
| CITY SUGAR | Leonard Brazil | Stephen Poliakoff | |||
| MACBETH | Malcolm | Glen Walford |
| Other THEATRE work includes: |
| 1994/05 | THE CHILDREN’S HOUR | Dr Joseph Cardin | Howard Davies | Royal National Theatre | |
| 1991 | BROADWAY BOUND | Stanley | David Taylor | Greenwich Theatre | |
| 1990 | THE SINGLE MAN | Warris Hussein | Greenwich Theatre | ||
| 1990 | MORE THAN ONE ANTOINETTE | Debbie Shewell | Monstrous Regiment/Young Vic | ||
| 1988 | THE MAD WOMAN OF CHAILLOT | The Broker | Lilian Baylis Theatre | ||
| 1988 | UNSUITABLE FOR ADULTS | Nick | Bristol Old Vic Studio | ||
| 1988 | THE DARKENING FIELDS | Peter Gill | National Theatre Studio | ||
| 1987 | THE RULING CLASS | Dinsdale Gurney | Liverpool Playhouse | ||
| BLOODY POETRY | William Polidori | Leicester Haymarket & Hampstead Theatre | |||
| DEAD ROMANTIC | Luke | Debbie Shewell | Soho Poly | ||
| LOOT | Sue Pommeroy | Croydon Warehouse | |||
| JOHN, PAUL, RINGO, GEORGE AND BERT | Brian Epstein | David Toguri | Young Vic |
William’s radio work is extensive and he is probably best known as ‘Dr. Richard Locke’ in THE ARCHERS. He narrated TULIP FEVER by Deborah Moggach for the Book at Bedtime Slot on BBC R4 and is one of the readers for SOMETHING UNDERSTOOD on BBC R4. Most recent radio includes:
| 2010 | MUGABE: GOD’S PRESIDENT | Ian Smith | Jeremy Mortimer | BBC R4 | |
| 2006 | THE LIFE OF HENRY BLOGG | Narrator/Green Sea Captain | Jeff Capel/ Andrew Barnes | BBC Schools Radio | |
| 2005 | PERSIAN FIRE | Reader | Louise Armitage | BBC R4 | |
| 2005/7 | THE NO. 1 LADIES DETECTIVE AGENCY | Dr Moffat | Gaynor Macfarlane | BBC R4 | |
| 2003 | THREE FIVE SILLY TWERP | Son | David Ian Neville | BBC R3 | |
| 2003 | VOICES OF THE OLD SEA | Reader | Liz Allard | BBC R4 | |
| 2002 | DEATH OF A VILLAGE | Mildmay | Peter Leslie Wild | BBC | |
| 2001 | VOICES FROM BEHIND THE CANVAS | Reader | Julia Butt | BBC R4 | |
| 2000 | VICTORIAN MARRIAGE BEDS | John Cross | Peter Leslie Wild | BBC R4 |
| 2010 | DEAD LIKE YOU by Peter James | Reader | Alexa Moore | Macmillan Publishers | |
| 2009 | DEAD TOMORROW by Peter James | Reader | Alexa Moore | Macmillan Publishers | |
| 2006 | DEAD SIMPLE by Peter James | Reader | Alexa Moore | Macmillan Publishers | |
| 2001 | THE MONEYMAKER | Penguin Books/Pearson Education | |||
| 2001 | TALES & MYSTERY & ADVENTURE | Pearson Education | |||
| 2001 | DAZZLER by Darren Gough | Penguin Books | |||
| 2000 | MORGAN’S RUN by Colleen McCullough | Chivers Press | |||
| 1996 | ERROR OF JUDGMENT by Dexter Dias | Chivers Press | |||
| 1995 | KING SOLOMON’S CARPET by Barbara Vine | Penguin Books | |||
| 1995 | FOR KICKS by Dick Francis | Penguin Books | |||
| 1992 | BUCCANEER by Dudley Pope | Chivers Press | |||
| 1991 | CONVOY by Dudley Pope | Chivers Press | |||
| 1991 | TALKING IT OVER by Julian Barnes | Random Century | |||
| 1991 | NEVER PICK UP HITCHHIKERS by Ellis Peters | Chivers Press | |||
| 1989 | THE BRIDESMAID by Ruth Rendell | Chivers Press | |||
| 1989 | RAT KING by Michael Dibdin | Clio Press Ltd |
William can also be heard narrating various audio-cassette recordings from the collection of SHARPE books by Bernard Cornwell.