• Navy ‘Theory’ cashmere roundneck jumper

    Navy ‘Theory’ cashmere roundneck jumper. Condition is Used. Dispatched with Royal Mail 2nd Class.
    £7.50
    3 bids
    £2.90 postage
    Ending Today at 8:59AM BST16m 55sColour: BlueMaterial: Cashmere
  • Authentic Theory Black Silk Sleeveless Top Size S 8 (P/TP)

    Authentic Theory Black Silk Sleeveless Top Size S 8 (P/TP) In great condition.
    £12.00
    1 bid
    £3.48 postage
    Ending Today at 8:53PM BST12h 11mClick & CollectColour: BlackMaterial: Silk
  • Theory Ladies Dress

    Theory Ladies Dress. Condition is New with tags. Dispatched with Royal Mail Second Class.
    £17.50
    Click & Collect
    £2.90 postage
    Colour: Black
  • THEORY Ladies Relaxed Striped Slip Dress In White/Grey Size UK 12. US Size 8.

    THEORY Ladies Relaxed Striped Slip Dress In White/Grey Size US 8/UK 12. Pit to pit 18 inches. Length 56 inches Cut on the bias so flows really well. B neck sleeveless. With undress dress. one side has a slit up the side as a feature if this really lovely relaxed dress. Cost over £300 new Condition is Very good Dispatched with Royal Mail recorded
    £24.99
    0 bids
    £3.90 postage
    Ending Wednesday at 1:26PM BST2d 4hClick & CollectColour: GreyMaterial: Polyester
  • New listingTheory Navy Blue Trench Rain Mac Coat Size S 8 10

    Theory Navy Blue Trench Coat. Size S 8 10. The label stated SP which is small petite. two pockets and is unlined.
    £13.00
    0 bids
    £4.20 postage
    Ending Sunday at 6:02PM BST6d 9hClick & CollectColour: Blue
  • Theory Ladies Jacket UK Size 8 (US4) in Blue And White Stripe

    Theory Ladies Jacket UK Size 8 (US4) in Blue And White Stripe. Condition is Used. Great condition see photos! Dispatched with Royal Mail 2nd Class.
    £11.99
    Click & Collect
    £5.00 postage
    Colour: White
    or Best Offer
  • THEORY SIZE P/TP/SMALL GREY 100% WOOL DOUBLE CARDIGAN

    DARK GREY CARDIGAN WITH MOCK LIGHTER GREY UNDERNEATH .
    £3.99
    0 bids
    £3.65 postage
    Ending Today at 7:19PM BST10h 36mColour: GreyMaterial: Wool
  • THEORY SHORT SLEEVE YELLOW CARDIGAN SIZE UK 6/8

    VERY SOFT AND COSY. THEORY SHORT SLEEVE CARDIGAN. IN MY OPINION VERY GOOD CONDITION. SIZE UK 6/8. LENGTH 28.5". TWO FRONT POCKETS.
    £5.00
    1 bid
    £2.70 postage
    Ending Thursday at 6:28PM BST3d 9hClick & CollectColour: YellowMaterial: Cashmere
  • Theory Ladies Jacket UK Size 8 (US4) in Light Grey

    Theory Ladies Jacket UK Size 8 (US4) in Light Grey in excellent condition with no sign of wear. Dispatched with Royal Mail 2nd Class or local collection from Maidenhead.
    £12.00
    Click & Collect
    £3.00 postage
    Colour: Grey
    or Best Offer
  • THEORY Breton stripe silk vest top - SMALL

    This is a lovely silk top from THEORY which is slightly A-line and very flattering. Great for layering over another vest top or under a long cardigan jacket.
    £20.00
    0 bids
    £3.45 postage
    Ending Today at 7:19PM BST10h 37mClick & CollectMaterial: Silk
  • New listing New Navy Linen THEORY Pants Trousers S/P

    Lovely dark navy pants by THEORY in a slightly stretchy linen mix. Perfect unworn condition. Waistband elasticated at the back. Two side slide pockets. Composition is 62% Linen, 36% Viscose and 2% Elastane.
    £12.99
    0 bids
    £4.95 postage
    Ending Friday at 9:20PM BST4d 12hColour: Blue
  • THEORY Designer JALA Ruche Black Vest Size US 4/UK 8-10 Rare

    Black stretch virgin wool-blend suiting designer fabric. Double-breasted button front and left flap side pocket. Fully lined in white satin fabric. Made of 88% Wool,10% Polyamide, 2% Lycra. pit to pit 42cm, length 68cm.
    £30.00
    0 bids
    £4.00 postage
    Ending Wednesday at 9:36PM BST2d 12hClick & CollectColour: Black
  • Theory Blouse Size L

    Theory Blouse Size L. Condition is Used. Dispatched with Royal Mail 1st Class.
    £8.50
    0 bids
    £3.48 postage
    Ending Today at 3:39PM BST6h 57m
    or Best Offer
    Click & CollectColour: BlueMaterial: Silk Blend
  • New listingBNWT THEORY Linen Pants Trousers S/P

    Perfect unworn condition. Waistband elasticated. No pockets. Composition is 58% Linen, 41% Viscose and 1% Elastane. Bought for myself but never worn. Length 92cm / 36in.
    £15.00
    0 bids
    £4.95 postage
    Ending Friday at 9:19PM BST4d 12hColour: White
  • Orange/Red Theory Dress - Mid Length

    Orange/Red Theory Dress . Dispatched with Royal Mail 1st Class.
    £1.70
    1 bid
    £5.73 postage
    Ending Today at 11:36AM BST2h 53mColour: Orange
  • Theory Shift Dress Size 12 Mint Green

    £1.90
    0 bids
    £3.48 postage
    Ending Friday at 3:59PM BST4d 7hColour: GreenMaterial: Polyester
  • Real Leather Theory Skirt

    Real Leather Theory Skirt. Condition is Used. Worn under 5 times, no flaws or stains. Authentic Theory brand skirt, retail price was $500.
    £20.00
    Colour: Black
    £4.00 postage
    Material: Leather
  • THEORY Wool Long Coat, Satin Lined, Size L

    Outer shell, 100% wool. Inner lining is satin. The Kooples. Ralph Lauren. Marc Jacobs. Tory Burch.
    £20.00
    0 bids
    £10.00 postage
    Ending Today at 7:46PM BST11h 3m
    or Best Offer
    Click & CollectColour: Ivory
  • Theyskens Theory Jasma Jacket Blazer Silk Mix Forest Green Split Collar US8 UK12

    Theyskens Theory silk blend Jasma jacket in Forest Green. Gently worn. Excellent condition. The size is US8 / French 42 / UK12. Fabric looks and feels like silk. Features the signature split collar.
    £15.00
    0 bids
    £4.75 postage
    Ending Thursday at 7:40PM BST3d 10hColour: Green
  • THEORY Black V Neck Long Sleeve Elegant Top M UK 12

    THEORY Black V Neck elegant long sleeved top M UK 12. M ix of Rayon Nylon Spandex.Very good condition well looked after.
    £4.99
    0 bids
    £5.45 postage
    Ending Today at 8:15PM BST11h 33mColour: Black
  • Theory Designer Suede Natural Overcoat

    Theory Designer Suede Natural Overcoat . Dispatched with Royal Mail 2nd class. Excellent condition! Bought in a sample sale and never worn.
    £49.00
    0 bids
    £5.00 postage
    Ending Wednesday at 7:39PM BST2d 10h
    or Best Offer
    Click & CollectColour: Beige
  • Theyskens Theory Dress S

    Theyskens Theory Dress S. Unworn. Beautiful summer dress. Has pockets. It’s slightly longer at the front than the back. I ve tried it on so you can see the length. I am 5’9 for reference. Dispatched with Royal Mail 1st Class.
    £24.99
    0 bids
    £5.73 postage
    Ending Today at 11:44AM BST3h 1m
    or Best Offer
    Click & CollectColour: BlueMaterial: Silk
  • Designer Silk Dress From Theory, Cream/Ivory. Size 2/UK8. Wedding;Formal.

    Stunning Designer Dress by Theory, Wedding, formal. The photos don’t do justice to how beautiful this dress is.
    £25.00
    0 bids
    £3.48 postage
    Ending Tuesday at 9:46PM BST1d 13h
    or Best Offer
    Colour: IvoryMaterial: Silk
  • Theory Wool Blend Dress - Size 2 - Black

    Theory Wool Blend Dress - Size 2 Sizing comes up small on this item so would say this is a size 8 UK 36" length Hidden side-zip closure. Lined. 60% wool, 36% polyester, 4% elastane. Few small clicks on front (see picture).
    £15.00
    0 bids
    £3.49 postage
    Ending Tuesday at 1:56PM BST1d 5h
    or Best Offer
    Click & CollectColour: BlackMaterial: Wool Blend
  • Theyskens’ Theory Grey Silk Maxi Skirt, SIze US10, IT44, UK12, Net A Porter

    Beautiful Skirt by Theyskens’ Theory. In great condition, so beautiful on, bit creased from storage. Measurements are: Waistband laid flat: 17” Length 41” Please drop me a message with any questions!
    £10.10
    0 bids
    £4.00 postage
    Ending 3 Jun at 4:36PM BST7d 7hClick & CollectColour: GreyMaterial: Silk
  • Theory Women Sleevless Vest Size 0 / UK6

    Theory Women Sleevless Vest Size 0 / UK6. Condition is New with tags. Lovely vest, see pictures for measurements, pockets are fake . Dispatched with Royal Mail 1st Class.
    £1.10
    0 bids
    £2.90 postage
    Ending Saturday at 6:36PM BST5d 9hColour: BlackMaterial: Viscose
  • New listingTheory Red Wool Dress US 6/ UK 10 £269 NEW

    Theory red wool sleeveless dress with fitted top, pleated skirt, back zip fastening and side slit pockets. Classic Theory Dress Thick wool dress, fully lined size US 6/ UK 10. Hardly worn and is great condition, cost £269 new. All items come from a smoke free home.
    £32.99
    0 bids
    £3.00 postage
    Ending Sunday at 6:25PM BST6d 9h
    or Best Offer
    Click & CollectColour: RedMaterial: Wool
  • THEORY Khaki/taupe Dress Size M

    THEORY Khaki/taupe Dress Size M Has been worn and dry cleaned but in good general condition There is a small mark which I’ve photographed Ramie fabric mix gives a nice faint texture to dress Approx measurements from armpit to armpit 46cm, and waist unstretched 39cm - 43cm stretched (all figures doubled around) And back of neck to bottom 86cm
    £17.50
    Click & Collect
    £4.00 postage
    Colour: Green
    or Best Offer
  • THEORY navy white star print silk shirt S 8

    THEORY navy white star print silk shirt S 8 . 100% silk great condition Dispatched with Royal Mail 1st Class.
    £14.99
    0 bids
    £3.48 postage
    Ending Saturday at 7:52PM BST5d 11h
    or Best Offer
    Click & CollectColour: WhiteMaterial: Silk
  • Olivier Theyskens Theory Wide Leg Pleated Trousers size US4 Brand New Never Worn

    Olivier Theyskens Theory Wide Leg Pleated Trousers size US4 Brand New Never Worn. Dispatched with Royal Mail 1st Class.
    £10.00
    0 bids
    £3.48 postage
    Ending Today at 8:03PM BST11h 21m
    or Best Offer
    Click & Collect
  • Gorgeous Theory Summer Dress

    Gorgeous Theory Summer Dress. Perfect for the current sunny weather or a beach holiday. I am size 10 and it fits perfectly, but it’s a loose fitting style so could suit size 6/8 too! Bought from Selfridges and only worn twice.
    £15.00
    0 bids
    £3.48 postage
    Ending Friday at 12:21PM BST4d 3h
    or Best Offer
    Click & CollectColour: White
  • New listingTheory Classic White Shirt L RRP £175 BNWT

    Theory white cotton classic white shirt. Generous cut. 72% cotton, 23% nylon, 5% spandex. Length 83cm. Underarm to end of cuff 52cm.
    £45.00
    0 bids
    £3.50 postage
    Ending Sunday at 10:35AM BST6d 1hClick & CollectColour: White
  • Theory Women’s Silk Dress

    Theory Women’s Silk Dress. Condition is Used. Dispatched with Royal Mail 1st Class.
    £20.00
    0 bids
    £3.48 postage
    Ending Today at 8:08PM BST11h 25m
    or Best Offer
    Click & CollectColour: PinkMaterial: Silk
  • THEORY silk navy and white star print trousers S 6 8

    THEORY silk navy and white star print trousers S 6 8. 100% silk Condition is Used but as new condition i am also selling the matching shirt! Dispatched with Royal Mail 1st Class.
    £16.99
    0 bids
    £3.48 postage
    Ending Saturday at 7:57PM BST5d 11h
    or Best Offer
    Click & CollectColour: WhiteMaterial: Silk
  • Theory Size S Beige Top BNWT

    Theory Size S Beige Top BNWT.
    £29.99
    0 bids
    £3.48 postage
    Ending Saturday at 9:53PM BST5d 13h
    or Best Offer
    Click & CollectColour: Beige
  • Theory Linen Shirt Dress

    Theory Linen Shirt Dress with belt and pockets. Exclusive for Bergdorf Goodman. Size is US4/UK 10
    £33.00
    Click & Collect
    £4.55 postage
    Colour: Black
    or Best Offer
    16 watching
  • Theory Grey Mesh Jumper

    Theory Grey Mesh Jumper. Worn about 5 times in all, but please note that because of the fabric there are some pulls on the fabric but nothing I would consider significant. Condition is Used. Dispatched with Royal Mail 1st Class.
    £19.00
    0 bids
    £3.48 postage
    Ending Today at 8:08PM BST11h 25m
    or Best Offer
    Click & CollectColour: Grey
  • THEORY Black/white Top. Size12-14. Worn Only Once

    THEORY Black/white Top. Size12-14. Worn Only Once. Condition is Used. Dispatched with Royal Mail 1st Class.
    £1.10
    1 bid
    £3.48 postage
    Ending Tuesday at 11:35AM BST1d 2hColour: BlackMaterial: Viscose
  • Theory Womens Trousers - Ivory - Size 2 (US)

    Elegant ivory trousers from American brand Theory New with tags Side pockets with additional key/coin pockets on both sides (hopefully you can see this in the second to last photo) Front zip and catch Back pockets Size 2 (US), so a UK 8 I have taken a photo (second photo) of a mark I have put on the front of trousers but this will come out with dry cleaning. Thanks for looking!
    £20.00
    Click & Collect
    £3.00 postage
    Colour: Ivory
    or Best Offer
  • theory dress

    theory dress purchased from HarveyNichols Knightsbridge Condition is New with tags. purchase price as shown on label £190 Fits size 8 an absolutely stunning dress on. Dispatched with Royal Mail 1st Class.
    £35.00
    0 bids
    £5.73 postage
    Ending Thursday at 7:35PM BST3d 10h
    or Best Offer
    Click & CollectColour: BlueMaterial: Cotton
  • New listingTheory Designer Pinafore Dark Denim/Cotton Mini Dress-Size US 4 UK 8-10 RRP £228

    Condition is Used. Theory pinafore jumper dress, size US 4 but would fit a UK 8-10 as an oversized dress. Dark blue, soft cotton fabric, almost denim in appearance with silk blend.
    £9.99
    1 bid
    £3.98 postage
    Ending Sunday at 6:36PM BST6d 9hClick & CollectColour: BlueMaterial: Cotton
  • THEORY wide leg wool trousers size 6 UK10 --USED ONCE-- black Wool Blend pockets

    THEORY wide leg wool trousers size 6 UK size 10 black Wool Blend Front pockets Back pockets --USED ONCE-- like new condition
    £39.99
    Click & Collect
    £3.49 postage
    Colour: Black
  • BNWT Theory Blue Blouse size M

    £55.00
    Colour: Blue
    £3.70 postage
    Material: Viscose
  • Theory Smart Trousers

    Theory Smart Trousers. Dispatched with Royal Mail 1st Class. Immaculate condition Very lovely fit Please check out my other items :)
    £18.00
    Click & Collect
    £3.45 postage
    Colour: White
    or Best Offer
  • NEW! £265 THEORY Malt Beige 100% Silk ‘Eilliv’ Button Up Ruffle Shirt Size S Top

    Colour: Malt Beige. -100% SILK BUTTON UP RUFFLE DETAIL SHIRT. - More information: Stunning top. Lovely quality silk and design. Arm: 62 cm. Length: 70 cm. -Size: S (larger cut).
    £60.00
    Click & Collect
    Free postage
    Colour: BeigeMaterial: Silk
  • THEORY Cream Elegant Tuxedo Wedding Ocassion Blazer Small

    THEORY Cream Elegant Tuxedo Blazer Sz6. Would fit sizes 6-8. Fitted and well cut, for any occasion. Worn once!
    £49.00
    Colour: Ivory
    Free postage
  • Theory Silk Top SzL

    Theory Silk Top SzL. Condition is Used. Dispatched with Royal Mail 1st Class.
    £10.00
    0 bids
    £3.48 postage
    Ending Thursday at 3:52PM BST3d 7h
    or Best Offer
    Click & CollectColour: BlackMaterial: Silk
  • New listingTHEORY Black Cotton Cashmere Poncho Jumper Small Net-A-Porter

    Size Small.
    £55.00
    0 bids
    £4.45 postage
    Ending Sunday at 6:56PM BST6d 10hClick & CollectColour: BlackMaterial: Cotton

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